These thick, fudgy homemade cosmic brownies are 10x better than storebought and went TikTok viral with over 13 million views! Topped with a creamy homemade chocolate ganache (made without heavy cream!) and rainbow chip sprinkles, these brownies are truly out-of-this-world delicious.
Be sure to read the post for important tips, step-by-step photos, a discount code for the rainbow sprinkles, and general FAQ's!
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Why These Homemade Cosmic Brownies are 10x Better Than Storebought
- Super Thick: Instead of the thin, store-bought Little Debbie brownies, I developed this recipe to be THICK when made in a 9x13 pan! No paper thin brownies here.
- Ultra Fudgy: The combination of melted butter, oil, cornstarch, an extra egg yolk, and Hershey's cocoa gives it that iconic fudgy Cosmic Brownie texture.
- Simple ganache without heavy cream: While most cosmic brownie recipes require you to use heavy cream for the frosting, I very rarely have it stocked in my fridge. So I really wanted to develop this recipe using a milk & butter ganache so that you can skip that extra step to the store (it's a bit softer in texture than ganache using cream) but tastes just as good...if not better! I also have a rich brownie frosting, if you're wanting to avoid the ganache all together!
- Tastes WAY Better: I hate to say it but the cosmic brownies I loved as a kid just don't taste the same anymore (they taste like plastic and not like chocolate!). This homemade version has a rich, fudgy chocolate flavor that you'll love.
Watch my viral Tiktok video below!
Copycat Cosmic Brownie: Tips for Success
- Mix by hand: The secret to fudgy brownies is to mix the brownies by hand so that you don't whip too much air into the batter. If you do use an electric mixer, beat it on a very slow speed and only mix until just combined.
- Use a light-colored metal pan, lined with parchment: Glass pans bake too slow and can cause the edges to overbake and get hard before the center fully bakes. While dark-colored pans will bake brownies too fast, causing dry and overbaked brownies (that can taste bitter). A light-metal 9x13 pan is what I recommend for this recipe.
- Refrigerate the bars after frosting: Since we're doing a simple ganache using butter & milk, the ganache won't be as "hard' at room temperature than a traditional ganache would be (scroll for more notes on the ganache!). So I recommend storing the frosted brownies in the fridge if you don't want the frosting to soften.
- Use a high quality cocoa powder: I tested this recipe using Hershey's 100% Cacao Natural Unsweetened Cocoa powder, as it's my favorite cocoa for brownies. I highly recommend using this exact brand or another high-quality cocoa, as "off brands" or cheaper cocoa often tastes like "fake chocolate" and will not taste good (you've been warned!). If you use a different brand or type of cocoa, just take note that the taste, texture, and appearance may significantly change.
Homemade Cosmic Brownie Ingredient Overview:
This is just an overview, click here to jump down to full recipe card for the recipe amounts and condensed recipe instructions.
- Unsalted Butter (you will be melting this so no need for it to be softened to room temperature!)
- Granulated Sugar & Brown Sugar
- Eggs: You'll need 3 eggs + 1 extra yolk (to make the brownies nice & chewy!)
- Vanilla Extract
- Vegetable Oil: The oil also keeps the brownies moist & fudgy (if you leave it out, your brownies will be more cake-like and dry).
- Cornstarch: This is the other secret ingredient to moist & fudgy brownies! If you have a corn allergy, you can leave it out.
- Salt
- Baking Soda
- Hershey's Cocoa Powder: I tested this recipe using Hershey's 100% Cacao Natural Unsweetened. I highly recommend using this exact brand or a high quality cocoa, as "off brands" or cheaper cocoa does not often taste good (you've been warned!).
- All-Purpose Flour
- Rainbow Chip Sprinkles: you can get these on Amazon (some craft stores & grocery stores also carry them!).
- For Chocolate Ganache: Semi-sweet chocolate chips (see next section for notes on brands!), butter, milk (ideally whole milk or 2% but more notes on milk in the recipe card "notes" section below).
Love this copycat recipe for Cosmic Brownies & craving more? I'm working on a new series of Little Debbie recipes, but in the meantime check out my Homemade Oatmeal Creme Pies and quick Homemade Star Crunch recipe that you can make in the microwave!
Where to buy the sprinkles?
I get my rainbow chip sprinkles on Amazon! It's a big, bulk-sized bag that will last you for a while! It also comes with a resealable bag for easy storing.
And! You can use them on my other cosmic recipes: Fudgy Cosmic Brownie Cookies, Christmas Tree Brownies, or even just use as an ice cream topping on my No Churn Chocolate Ice Cream!
Easy Chocolate Ganache Using Milk (i.e. without heavy cream!)
Read this important section for lots of notes & tricks!
Heavy Cream vs. Milk: I debated between using heavy cream or milk for this ganache but since I rarely have heavy cream in my fridge...I figured most of you don't either! So I opted for ease & simplicity and developed this recipe using milk and butter instead (the butter replaces the fat from the heavy cream!). The result is a smooth, creamy frosting that is so delicious and soft.
Chill To Firm Ganache: Because we're not making a traditional ganache with heavy cream, the frosting won't totally harden at room temperature so it's important to chill the finished brownies. After spreading the frosting on the brownies, refrigerate for 1-2 hours for the frosting to set (do this before cutting, if you're trying to get clean edges!). The ganache will start to soften at room temperature, so I recommend storing them in the refrigerator to keep it firm.
Differences In Chocolate Chip Brands: We also found that the brand of semi-sweet chocolate chip you use will impact how firm the ganache sets up in the fridge. We tested this ganache using 4 different common semi-sweet chocolate chip brands. Nestle Toll House was #1 in producing the firmest ganache, Ghiradelli #2, Hershey's #3, Costco brand #4. All are comparable taste-wise (I like the flavor of Ghiradelli the best!) but they all do firm up a bit differently.
Want a more firm ganache that hardens? If you want the frosting to stay "hard" at room temperature, you will need to use heavy cream. To make a firm ganache, follow the instructions in the recipe card below but use ½ cup heavy cream and 1.5 cups chocolate chips (no butter).
How To Make Cosmic Brownies (step by step photos!)
This is just an overview showing step-by-step photos, click here to jump down to full recipe card with exact instructions.
Step 1: Melt Butter & Sugars, then Mix Brownie Batter
Preheat the oven to 350° degrees. Follow the instructions in the recipe card below to make the brownie batter, carefully reading each step (take note that you will be melting the butter and sugars together at first!).
Step 2: Spread Into Pan
Spray a light-colored metal 9x13 pan with nonstick cooking spray, then press on a piece of parchment paper to cover the bottom and long sides to create a "parchment sling". This will help you lift the brownies out of the pan so that you can cut them nicely. Spread brownie batter into the prepared pan until smooth.
Note: baking these in glass or dark metal pans may cause them to overbake and become bitter. If that's the only pan you have, lining with parchment on all sides becomes more crucial. You will also likely need to bake them for less time to prevent overbaking.
Step 3: Bake
Bake for 24-26 minutes and let them cool completely before adding any glaze or frosting. After the pan is no longer hot to the touch, you can also speed up the cooling process by placing the pan in the fridge. In the meantime, move to step 4 to make the chocolate ganache!
Tip: Be careful not to overbake the chocolate brownies! Check to make sure they are done by inserting a toothpick into the middle or gently shaking the pan to ensure the center is not jiggly. If the toothpick comes out clean, then they are finished baking. If you bake them too long, they won't have the irresistible fudgy texture you want.
Step 4: Make Easy Ganache
While the brownies are cooling, prepare the easy chocolate ganache! In a medium-sized bowl, place chocolate chips and chopped butter. In a separate medium-sized bowl or large liquid measuring cup, heat milk in the microwave for 2 minutes (it's important that your measuring cup or bowl is at least 3x taller than the milk line, as it will expand when it's heating and can easily overflow). You can also heat this on the stove; remove once it begins to steam.
Use a hot pad to carefully remove milk from the microwave and pour over the chocolate chips and butter (do not stir yet!). Allow to sit on the counter for about 3 minutes, then stir until smooth and creamy. It may take a few minutes for it to come together; it often looks separated at first. Allow to cool for about 30 minutes before pouring over cooled brownies.
Step 5: Decorate Brownies
Once brownies are cooled, give the ganache a quick stir then spread over the brownies. Immediately top with rainbow chip sprinkles (or any other sprinkles you have!). Place in refrigerator for 1-2 hours to help the frosting harden (you can speed this up by putting in the freezer!).
Tip: As I said earlier in this post, this frosting is made without heavy cream so it's not going to totally harden at room temperature. This is why I recommend storing the brownies in the fridge after frosting.
Step 5: Cut & Enjoy!
If you want really clean edges & slices, you will need to refrigerate the frosted brownies for at least 2 hours for the frosting to set. Or freeze for an hour. It's best to cut these straight from the fridge or freezer, as that is when you'll get the cleanest slice.
After they sit out at room temperature, the frosting will start to get softer so I recommend storing in the fridge if you want them to stay looking fresh & fine ;)
Tip: To get a clean edge, use a large chef's knife, cut straight down, then wipe off in between each cut (do not "saw" through the brownies back in forth). This will help you get that crisp cut like the real Little Debbie cosmic brownies!
Storage & Freezing
How long do these fudgy brownies last?
In order for the brownies to last the longest (and keep their amazing taste & texture), I suggest you store them in an airtight container for 3-4 days. If you want the frosting to stay hardened, store them in the refrigerator. If stored properly, they'll stay good for 4-5 days.
Can cosmic brownies be frozen?
They sure can! The fudgy texture & soft frosting actually makes these so good out of the freezer (they're not rock hard!). If you want to keep the frosting looking nice, freeze the brownies (unwrapped and uncovered) for 1-2 hours then transfer them to an airtight container. This will allow the frosting to freeze so that it doesn't smudge when you store them.
These fudgy brownies will keep in the freezer for 1-2 months (any longer, and they tend to dry out).
Dietary Variations
- Gluten Free: I have tested this recipe using Bob's Red Mill 1-to-1 Gluten Free All-Purpose Flour and I thought the results were great (they're a bit less fudgy but a couple friends couldn't tell they were gluten free!). Since I used a gluten-free flour that is a 1:1 replacement, you can use the same amount of regular flour in place of it. If you make this gluten free, be sure to let me know how it worked and how you liked it! ***Be sure to check that your rainbow chips are gluten-free, as some brands are not (Sweetapolita's are GF - use promo code “DESIGNEATSPRINKS15“ for 15% site-wide!)
- Dairy Free: I will put a disclaimer on this that I have not tried this recipe dairy free, so if you try it be sure to report back! But if you read the comments, some have reported using almond milk or nutpods with success! To make it dairy free, you'll need to swap out the butter and chocolate. Some people that are dairy-free prefer to use clarified butter, or ghee since it is free of lactose and qualifies as dairy-free. Otherwise, you can also try replacing the butter with equal parts coconut oil or vegan butter. To swap out the chocolate, Enjoy Life chocolate chips are dairy-free! They have a variety of chocolate chips, including dark chocolate.
- Egg Free: I am not familiar with vegan or egg substitutes but until I have a chance to test these, you might try out Crazy Vegan Kitchen's version! I'd love to know how ya'll turn this recipe into egg free or vegan cosmic brownies!
Frequently Asked Questions:
I tested this recipe using Hershey's 100% Cacao Natural Unsweetened. I highly recommend using this exact brand or another high-quality cocoa, as "off brands" or cheaper cocoa often tastes like "fake chocolate" and will not taste good (you've been warned!). If you use a different brand or type of cocoa, just take note that the taste, texture, and appearance may change.
The real Little Debbie cosmic brownie sprinkles are called "rainbow chip sprinkles" but you can also just use mini M&M's! I've included a few places below where you can find rainbow sprinkle sprinkles.
Amazon: You can get Wilton rainbow chip sprinkles on Amazon
Sweetapolita: use promo code “DESIGNEATSPRINKS15“ for 15% site-wide! Search "bit chips" on her site for the cute options...she even has pastel ones!
Craft stores like Michaels or Joanns also often have them! A reader also mentioned they've seen them at Walmart!
Grocery Stores: If all else fails, grab a box of Pillsbury Funfetti brownies and use the packet inside (then save the brownie mix for another time).
To ensure your brownies are dense & chewy, I recommend mixing this by hand! Using an electric or stand mixer will make it quicker, but be sure not to beat the batter very much!
Be sure to read the post above for more specifics about this easy ganache or see my chocolate chip comparison post! The short answer is no, because we're using milk & butter instead of heavy cream, these will not completely harden at room temperature so you'll want to store them in the fridge if you want the frosting to stay looking nice.
If you want the frosting to stay "hard" at room temperature, you will need to use heavy cream. To make a firm ganache, follow the instructions below but use ½ cup heavy cream and 1.5 cups chocolate chips (no butter).
I personally like the taste of the milk & butter ganache (it's creamier & tastier) but if you need to transport these or stack (between parchment paper), it's best to use a traditional chocolate ganache that uses heavy cream.
Cosmic brownies are a popular packaged treat in the United States consisting of a thin, fudgy brownie with a chocolate coating and rainbow sprinkles. Made by the company "Little Debbie", cosmic brownies & their whole array of snack treats are nostalgic childhood lunchbox treats that can be found at most grocery stores or gas stations in the US. I've gotten this question from people outside of the US so I figured I'd throw in a little info for my overseas friends!
Yes! You can see my smaller batch version here.
New! Cosmic Christmas Tree Brownies
Turn these cosmic brownies into adorable cosmic brownie trees for the holidays!
Homemade Cosmic Brownies (TikTok Viral)
Ingredients
- ¾ cup unsalted butter (i.e 1.5 sticks; you will be melting this)
- 1 ½ cups granulated sugar
- ½ cup light brown sugar
- 3 large eggs + 1 egg yolk
- 1 tablespoon vanilla extract
- 1 teaspoon salt
- ¼ teaspoon baking soda
- 2 tablespoons cornstarch
- 1 ½ cups Hershey's cocoa powder (100% cacao natural unsweetened) I highly recommend using this specific cocoa or another quality cocoa. Off-brand cocoa often tastes bad so use at your own risk...you've been warned!
- 1 cup all-purpose flour
- ¼ cup vegetable oil
Easy Chocolate Ganache (see notes section below for a firmer, traditional ganache using heavy cream)
- 1 ½ cups semi-sweet chocolate chips (i.e. 12 ounce bag) *see notes section below for notes on certain brands; we found Nestle Toll House or Ghiradelli brands firm up the best
- 6 tablespoons unsalted butter chopped into small cubes
- ½ cup whole milk (you can also use 2% or 1% but the ganache will be less firm so you will need to refrigerate and/or freeze brownies so frosting sets; see notes below)
Topping
- Rainbow chip sprinkles you can get the Wilton brand at most craft stores or on Sweetapolita (use code DESIGNEATSPRINKS15“ for 15% site-wide!)
Before you begin! If you make this, will you do me a huge favor and leave a review and rating letting me know how you liked this recipe? This helps my small business thrive so I can continue providing free recipes and high-quality content for you.
Instructions
To Make Brownies:
- Before you start, be sure to read through the tips & tricks in the post above for ingredient notes, step-by-step photos, and FAQ's!
- In a large microwave-safe bowl, add unsalted butter (¾ cup, i.e. 1 ½ sticks), granulated sugar (1 ½ cups), and light brown sugar (½ cup). Microwave for 2 minutes, stir, then microwave for 30 more seconds. Carefully remove bowl from microwave and stir until smooth. Let cool for 2-3 minutes.
- To the butter and sugar mixture, stir in the eggs (3 large), egg yolk (1 large), vanilla extract (1 tablespoon), salt (1 teaspoon), baking soda (¼ teaspoon), and cornstarch (2 tablespoons). Once combined, mix in cocoa powder (1 ½ cups) and all-purpose flour (1 cup) until just combined (I recommend mixing by hand to prevent from overmixing). Stir in vegetable oil (¼ cup).
- Spray a light metal 9x13 pan with nonstick cooking spray, then press on a piece of parchment paper to cover the bottom and long sides to create a parchment sling (photo in post above!). This will help you lift the brownies out of the pan so that you can cut them nicely. Spread brownie batter into the prepared pan until smooth.Note: baking these in glass or dark metal pans may cause them to overbake and become bitter. If that's the only pan you have, lining with parchment on all sides becomes more crucial. You will also likely need to bake them for less time to prevent overbaking.
To Make Easy Chocolate Ganache
- Before you begin: Note that the ganache will not completley "harden" as a traditional ganache with heavy cream would. See notes section below for tips & tricks, as well as an alternate recipe using heavy cream.
- In a medium-sized bowl, place semi-sweet chocolate chips (1 ½ cups) and chopped unsalted butter (6 tablespoons).
- In a separate medium-sized bowl or large liquid measuring cup, heat milk (½ cup) in the microwave for 1 ½ - 2 minutes, or until it begins to bubble (it’s important that your measuring cup or bowl is at least 3x taller than the milk line, as it will expand when it’s heating and can easily overflow). You can also heat this on the stove; remove it once it begins to steam.
- Use a hot pad to carefully remove milk from the microwave and pour over the chocolate chips and butter (do not stir yet!). Allow to sit for about 3 minutes, then use a whisk to stir until smooth and creamy. It may take a minute or two for it to come together; it often looks separated at first. Allow to cool for about 30 minutes before pouring over cooled brownies.
To Decorate:
- Once brownies are cooled, re-stir the ganache and spread over brownies. Immediately top with rainbow chip sprinkles (or any other sprinkles you have!). Place in refrigerator for 1-2 hours to help the frosting harden (you can speed this up by putting in the freezer!).Use a large knife to slice bars ( I highly recommend that your bars are chilled or frozen before slicing to ensure a clean cut).
- Storage: Refrigerate the frosted bars. You can also keep at room temperature for up to 1 day (just note the frosting will soften). They get even better & fudgier on Day 2!
Last Step! Please leave a review and rating letting me know how you liked this recipe! This helps my small business thrive so I can continue providing free recipes and high-quality content for you.
Brooke
LOVED these! They had a bit more dark chocolate taste than the OG, but I loved that about them. Mine were more fudge, less brownie- so I may have undercooked slightly, but they were raved about by everyone.
LOVE THIS SERIES!
Melissa
So glad you loved them, Brooke! Thank you so much for taking the time to leave a review. I appreciate it SO much!
Laura K
These are amazing!!! I followed to recipe (almost) completely. I did decide to use heavy cream for the ganache. I thought I’d messed up when I (by habit when making microwave fudge) poured the cold heavy cream in the chocolate chips before heating it. I decided what’s done is done. I popped the bowl into the microwave and let nature take its course. The ganache turned out perfect. Very smooth and creamy and the perfect consistency. I ordered my rainbow candy coated chips from a company that I usually buy nuts from. I only sprinkled them on half of the ganache covered brownies because my husband is a party pooper and doesn’t like anything added to his brownies. I could have covered them completely because he decided these aren’t the type of brownies he usually likes(he’s a box brownie dude). But I didn’t make these for him. My son’s fiancé shared this recipe and I made them for her. We both are both cosmic brownie fans. But these are so much better. The texture of the brownies are very similar but way richer in flavor. Needless to say they are a hit with the brownie snobs in my household. I will be making more along with the occasional box brownie mix to appease the box brownie king.
Melissa
So glad you all loved them, Laura! Makes my day to know I passed the brownie snob test, haha!
Thanks for taking the time to leave such a thoughtful review - I appreciate it so much!
Lisa
Tastes better than the original. The Grandkids absolutely loved them. Will definitely be making again but with a little less ganache on top.
Melissa
So glad you & the kiddos loved them, Lisa! Thanks for taking the time to leave me a note - I appreciate it so much!
angie
these were delicious! the best brownies i’ve ever had. the only thing i did different was i pretty much doubled the amount of heavy cream for the ganache and added a splash of vanilla, tastes great!
Melissa
So glad you loved them, Angie!
Thank you for taking the time to leave me a review - it helps my small biz so much & I really appreciate it!
JoAnna Hendershot
Was way to chocolatey but it was okay over all
Melissa
They are definitely a very rich brownie! Thanks for giving them a try & leaving your feedback!
Crystal
Absolutely amazing! I used different sprinkles but will definitely use the right ones next time. Turned out beautiful and delicious. Genius recipe!
Melissa
So glad you loved them, Crystal!
Thank you for taking the time to leave me a review - it helps my small biz so much & I really appreciate it!
olivia
currently on my second time making this. my mom kept bugging me to make these again. they taste like the real thing but better! we substituted with mini m&ms on top!
Melissa
Wow, it makes my day to know you loved them so much you already made them again! That makes all my 12 tests worth it, haha!
Thank you for taking the time to leave me a review - it helps my small biz so much & I really appreciate it!
Molly
Made these today and they are sooooo good! Made them with dairy free butter and milk and they're the ultimate lactose intolerant friendly brownies I've ever made!! This will be a regular bake for me now! Family loves them too!
Melissa
Wow, I'm so glad you loved them and were able to adapt them to DF so seamlessly! That makes me so happy to hear!
Thank you for taking the time to leave me a review - it helps my small biz so much & I really appreciate it!
Staci
Amazing!
Melissa
So glad you loved them, Staci!
Thank you for taking the time to leave me a review; I appreciate it SO much!
Nic
Does this work for high altitude too or are there any measurement changes needed to be made?
Melissa
Hi Nic! I haven't tested this in high altitude but I don't think you'd have to adjust much since it's a relatively dense recipe that won't rise much as it is. If you make them & feel like they're too puffy, you could try taking out the baking soda. Let me know if you try it and how they turn out!
Reilly
This recipe was so easy to follow and the brownies came out delicious!! Followed the tips video on tik tok which helped a lot. Will make again!
Melissa
I'm so glad you loved them & found the instructions helpful - that feedback makes my day!
Thank you for taking the time to leave me a review; I appreciate it SO much!
Lydia
I’ve made so many variations of brownies in the past but this has got to be the best brownie I’ve EVER made. So so good!
Melissa
YAY! That made my day...so glad you loved them!
Thank you for taking the time to leave a review - I appreciate it so much!
Jamie
Like how Melissa creates the most amazing recipes is AMAZING! I’m obsessed, these are the most moist delicious brownies I’ve ever had. Its also fun and easy to make! Definitely making more of her recipes!
Melissa
WOW thank you so much, Jamie! So glad you loved them & enjoy all my recipes. I appreciate your support so much!
Christine
OMG. This recipe is beyond good! The extra step of the chocolate ganache is so so good! My family adored these Brownies! A keeper for sure!
Melissa
So glad you & the family loved them, Christine! Thank you for taking the time to leave a review – I appreciate it so much!
Hello
Good ,really good .I had it w with some milk because it is VERY thicccc
Melissa
So glad you loved them! I agree, they are THICK and rich...milk is a good call!
Janey
Made these tonight and they are delicious 🤤 this is my go to recipe for brownies now!
Janey
I wanted to add that I cooked mine on a cookie sheet with the silicone baking mat on top of the cookie sheet. I also used coconut oil on the baking mat. I also used my kitchen aid to mix 😱 but it turned out fine lol. I see other complaining it was bitter but I didn’t think that at all! I don’t like super sweet stuff though so it may just be a preference to each their own 🤷♀️ thanks for posting this!
Melissa
You KitchenAid rebel, Janey! Haha JK, using a mixer super low & slow won't do much harm ;)
So glad you loved them. Thank you for taking the time to leave a review – I appreciate it so much!
Makayla
So beautiful and yummy, hands down the best ganache recipe I have tried in awhile! Thank you!
Melissa
So glad you loved them, Makayla! Thank you for taking the time to leave a review – I appreciate it so much!
Anonymise
I made this recipe for my friends, family, and teachers and they all LOVED them! I only used a teaspoon of vanilla because I didn't have enough for a full tablespoon, but they turned out amazing still!
Melissa
So glad you & the crew loved them! Thank you for taking the time to leave a review – I appreciate it so much!
Skittlez
I made it and its so freaking bitter you need to tweak your recipe even the frosting is bitter.
Melissa
Sorry this didn't work for you! They have quite a bit of sugar to cocoa ratio so they definitely shouldn't be bitter. I'd love to help you troubleshoot:
1. Did you bake it in a dark metal pan by chance? If so, these can bake too hot and overcook the sugar/cocoa which can taste bitter.
2. Did you line the pan with parchment?
3. What brand of cocoa powder and chocolate chips did you use?
Kate
The recipe came out very bitter. I don’t know what went wrong, I even used the Hershey’s cocoa. Everything I used was the exact amount. It just tasted like a dark chocolate cosmic brownie. Not my favorite.
Melissa
Hi Katie! I'd love to help you troubleshoot. They have quite a bit of sugar to cocoa ratio so they definitely shouldn't be bitter. That said, I just had one other person say that (out of hundreds who have loved them...so I'm a bit stumped!), so I'd love for you to let me know the following:
1. Did you bake it in a dark metal pan by chance? If so, these can bake too hot and overcook the sugar/cocoa which can taste bitter.
2. Did you line the pan with parchment?
3. What brand of chocolate chips did you use for the gananche?
Kate
I used a 13x9in aluminum disposable pans, and I did use parchment paper. And I used Nestle Toll House semi-sweet chocolate chips.
Melissa
Hmm! I haven't tried baking these in disposable pans but I don't think that would be an issue at all. Do you have an oven thermometer to know if your oven might run hot? (Mine runs about 50 degrees hot if I don't catch it.) Did your brownies seem a bit overbaked or crunchy on the edges? My only other thought is that maybe they got overbaked and bitter but it's hard for me to know without tasting them (if you happen to have a photo, you can DM me on Instagram!). This recipe does use a lot of cocoa powder so if there's an off chance you didn't add the right amount of sugar, that could also be a bitter brownie.
I don't think this is it (since I'm assuming it was more the brownie part that was bitter) but I personally find Nestle chocolate chips a tiny bit bitter tasting in ganache. But again, that was just because I did a taste test of 4 brands while testing this so I was being super picky haha!
All that said, I did have a few people say they thought the brownies were too rich/chocolately, so some may just have a different taste preference. I'm not saying yours weren't actually bitter but I do know some super chocolate recipes taste bitter to some people!