The BEST soft, fudgy, and chewy brownie cookies inspired by Little Debbie's cosmic brownies! Enjoy chilled for the perfectly fudgy & dense texture.
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Why I Love These Cosmic Brownie Cookies
- Super Fudgy & Dense: just like my copycat cosmic brownies, these cookies have a thick, dense, and super fudgy texture. The use of dark cocoa powder & the addition of a tiny bit of corn syrup helps give it this iconic chewy texture.
- Easy to make: these double fudge cookies are one of those cookies that look fancy but are actually easy to whip up! The ganache comes together quickly using the microwave (no stovetop needed!). No need to run to Crumbl next time you're craving one of these bad boys.
- A crowd favorite: Whether you're making them giant or scooping them into smaller, bite-sized cookies for holiday platters (see how I make them Christmas-themed below!), these are one of those cookies that everyone loves.
Ingredient Notes
- Cocoa Powder: I use and recommend Hershey's Special Dark Cocoa powder to give them a moist, rich flavor. You can substitute for regular unsweetened cocoa powder, just note that your cookies will have a puffier texture and won't have the iconic brownie taste.
- Rainbow chip sprinkles: You can find these at Michaels, Amazon, or one of my favorite budget-hacks is to get a box of Pillsbury Funfetti brownie mix (at most grocery stores!) and use the packet inside. You can then just keep the brownie mix for another time.
- Light corn syrup: We're using a small amount of corn syrup to create a chewy, dense, fudgy cookie. Omitting it will not result in the ideal texture, so I highly recommend using it (ps. light corn syrup is not the same as high fructose corn syrup!). You can find this in the baking aisle (Karo or generic brand works). If you can't find it where you live, you can try using thick honey or light molasses to achieve a similar texture (it won't be exact). Or you can use 1 tablespoon of milk but keep note that the cookies will likely end up puffier and won't have the same chewy, dense, fudgy texture.
- Heavy cream: In order to get a thick chocolate ganache that "hardens", you'll want to use heavy cream (also known as "heavy whipping cream" at grocery stores).
- Chocolate chips: I use semi-sweet chocolate chips but if you want a more subtle chocolate flavor, you can use milk chocolate chips.
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: Homemade Cosmic Brownies or even just use as an ice cream topping on my No Churn Chocolate Ice Cream!
How to Make Cosmic Brownie Cookies
This is just an overview showing step-by-step photos, jump to full recipe card with exact instructions.
Step 1: Make Cookie Dough
In a large bowl, use an electric mixer to mix together cookie dough. Dough should be thick and similar to a play-doh consistency, as shown below.
- Preheat oven to 350ยฐF.
- In a large bowl, use an electric mixer on medium-high speed to cream softened unsalted butter (ยฝ cup, 1 stick), light brown sugar(ยฝ cup), and granulated sugar (ยผ cup) for 2 minutes until light and fluffy.
- Add the egg (1 large), vanilla extract (1 teaspoon), and light corn syrup (2 tablespoons) and mix on low speed until combined. Scrape down the sides of the bowl so everything can combine.
- Add in baking soda (ยผ teaspoon) and salt (ยผ teaspoon) and mix for another 5-10 seconds until combined.
- Lastly, add dark cocoa powder (ยฝ cup) and all-purpose flour (1 ยผ cups) and mix on medium until combined.
Tip: Using softened butter is important here! If your butter is straight from the fridge, microwave for 10 seconds to slightly soften.
Step 2: Scoop, Flatten, Bake
Scoop dough into ยผ cup (4 tablespoons) sized scoops (I use this stainless steel cookie scoop!), roll into balls, then gently flatten each dough ball into a ยฝ" thick disc; this will help them spread instead of be puffy. Bake at 350ยฐF for 11-12 minutes, then allow cookies to fully cool before topping.
Tip: Baking on a parchment-lined, light-colored metal pan will allow your cookies to bake evenly without overbrowning. This is the trick to soft, chewy cookies!
Step 3: Decorate
After the cookies are cooled, spoon 1 tablespoon of chocolate ganache on each cookie and top with rainbow chip sprinkles.
Jump to full recipe card with exact instructions to make the ganache.
Step 4: Refrigerate & Enjoy!
Refrigerate the frosted cookies to help the ganache set. Chilling will also help them become even better & fudgier! You can also keep them at room temperature for up to 2 days, if desired.
Tips & Variations
- Make it holiday themed! Pick out the red, pink, and green rainbow chip sprinkles (shown below!) to make them Christmas-themed!
- Top with mini m&m's or sprinkles: Don't have rainbow chip sprinkles? You can also top with mini m&m's or any sprinkles of your choice!
- Have extra ganache? If you end up with a little extra chocolate ganache, stick in a ziploc bag in the freezer and then add to hot cocoa!
Frequently Asked Questions:
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Fudgy Cosmic Brownie Cookies (TikTok Viral!)
Ingredients
- ยฝ cup unsalted butter softened
- ยฝ cup light brown sugar
- ยผ cup granulated sugar
- 1 large egg
- 1 teaspoon vanilla extract
- 2 tablespoons light corn syrup Fun fact: this is not the same thing as high fructose corn syrup!
- ยผ teaspoon baking soda
- ยผ teaspoon salt
- ยฝ cup dark cocoa powder I use Hershey's Special Dark
- 1 ยผ cup all-purpose flour
Toppings:
- ยพ cup semi-sweet chocolate chips
- ยผ cup heavy cream
- rainbow chip sprinkles
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
- Preheat oven to 350ยฐF.
- In a large bowl, use an electric mixer on medium-high speed to creamย softenedย unsalted butterย (ยฝ cup, 1 stick),ย light brown sugarย (ยฝ cup), andย granulated sugarย (ยผ cup)ย for 2 minutes until light and fluffy.
- Add theย eggย (1 large),ย vanillaย extractย (1 teaspoon), and light corn syrup (2 tablespoons)ย and mix on low speed until combined. Scrape down the sides of the bowl so everything can combine.
- Add inย baking sodaย (ยผ teaspoon)ย andย saltย (ยผ teaspoon)ย and mix for another 5-10 seconds until combined.
- Lastly, addย dark cocoa powderย (ยฝ cup)ย andย all-purpose flourย (1 ยผ cups)ย and mix on medium until combined.
- Scoop dough into ยผ cup (4 tablespoons) sized scoops (I useย this stainless steel cookie scoop!), roll into balls, then gently flatten each dough ball into a ยฝ" thick disc; this will help them spread instead of be puffy.
- Bake at 350ยฐF for 11-12 minutes. Do not overbake. The centers may look a tiny bit wet but will continue to bake on the hot pan, allowing them to firm up without overbaking.Allow to fully cool before decorating.
To Make Chocoalte Ganache:
- In a medium-sized, heat-safe bowl (cereal bowl sized), placeย semi-sweet chocolate chipsย (ยพ cup).
- In aย separateย medium-sized bowl or large liquid measuring cup, heatย heavy creamย (ยผ cup)ย in the microwave for 30-45 seconds, or until it begins to bubble (itโs important that your measuring cup or bowl is at least 4x taller than the milk line, as it will expand when itโs 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 (do not stir yet!). Use a fork to press down the chips so that they're fully covered with the cream.Allow to sit for about 3 minutes, then use a fork to stir; it will be thick and will likely look like it's not going to mix together but keep at it until smooth & creamy.If your mixture doesn't melt down, microwave in 10 second increments at 50% power, stirring in between each increment until smooth.
To decorate:
- Spoon 1 tablespoon of chocolate ganache on each cookie and top with rainbow chip sprinkles. Place in refrigerator for 30-60 minutes to help the ganache harden.
- I recommend refrigerate the cookies as they get even better & fudgier when chilled! You can also keep them at room temperature for up to 2 days, if desired.
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.
Notes
- Smaller cookies: For smaller cookies, use a 2-tablespoon scoop and bake for 8-10 minutes.
- Cocoa Powder: I use and recommend Hershey's Special Dark Cocoa powder to give them a moist, rich flavor. You can substitute for regular unsweetened cocoa powder, just note that your cookies will have a puffier texture and won't have the iconic brownie taste.
- Rainbow chip sprinkles: You can find rainbow chip sprinkles at Michaels, Amazon, or one of my favorite budget-hacks is to get a box of Pillsbury Funfetti brownie mix (at most grocery stores!) and use the packet inside. You can then just keep the brownie mix for another time.
Cheryl Ratcliff says
Have you ever mailed these? My granddaughter picked this recipe out for cookies she wanted. She is away at college.
Melissa says
I haven't mailed these but I think they will hold up well, as long as you don't live in a hot place where the ganache would melt!
Nicole says
The recipe was clear, the cookies were delicious!
Steph says
Came out perfect. Excellent instructions.
Melissa says
Thank you so much for leaving a review, Steph!
Heather G says
This recipe turned out beautifully and it was so delicious! The directions are clear, the pictures are great. I will definitely make these again! Note: I made these using black cocoa and it turned out amazing!
Melissa says
Thank you so much for leaving a review, Heather! I really appreciate it!
Dottie says
Cookie was good and fun to make..the problem I had was the dough was too soft to handle..would like your opinion on what I did wrong. Thanks will make againโฆ
Melissa says
Hi Dottie! Hmm, this dough should be nice & thick! Did you use real butter or margarine?
Janice says
These cookies are ridiculously good and so easy to make. I made them for my mom for Valentines Day. โค๏ธ
Melissa says
So glad to hear you enjoyed this recipe, Janice! Thank you so much for leaving a review!
Kelsey Rayer says
Delicious cookies! They make over 8 depending on how big you make them. So yummy!!!
Melissa says
Thank you so much for leaving a review, Kelsey!
Abby says
Got a kitchen aid mixer for Christmas and decided to try baking for the first time ever. These are AMAZING. We are impatient and had one right after we put the ganache on, but they truly are 78x better cold from the fridge. Thereโs are a 10/10 and the recipe was easy to follow.
Melissa says
So glad to hear you enjoyed this recipe so much, Abby! Thank you so much for leaving a review, I really appreciate it! And happy baking with your new KitchenAid! :)
Emily says
I love this recipe and so does everyone I make it for! They are my new go-to cookies for any occasion.
I also appreciate that the ingredient amounts are listed within the recipe.
Melissa says
I am so happy to her you enjoy this recipe, Emily! Thank you so much for leaving a review, I really appreciate it!
Teresa says
Can these be pressed into an 8x8 pan and baked?
Melissa says
Yeah! I actually have a version of this dough for a 9x13, if you want to do that (just leave out the mint and use the cookie gananche). https://www.designeatrepeat.com/thin-mint-cookie-bars
Teresa says
Thank you so much! Will give them a try. ๐
Gaby says
These cookies came out perfect !! I tripled the recipe and it made 24 big cookies. I froze them for about thirty minutes before putting in the oven and they didn't spread much. I used dark chocolate chips instead of semisweet for the ganache because it's what I had and it complemented the cookies very well. The sprinkles that are linked are delightful; very reminiscent of cosmic brownies.
Melissa says
Yum, I'll have to try them out with dark chocolate chips for the ganache sometime! Thank you so much for leaving a review, Gaby! I really appreciate it!
Alison says
Is there a replacement for the corn syrup?
Melissa says
You can use a thick honey!
Josi says
Have you tested these in the freezer with the ganache? I want to make them for my brother n law for Christmas, but I want them to freeze nicely for him.
Melissa says
Yes I have and it freezes and thaws well!
Josi says
Thank you so much! I will make them Saturday and leave a review.
Josi says
My brother n law loved them. Thanks for the great recipe.
Josi says
What were the results of freezing them with the ganache? I am trying to figure out what to make my brother n law for Christmas and I thought he might love these, but I want to make sure what I make will freeze nicely for him.
Melissa says
They freeze and thaw nicely!
JennH says
Yum. Dense, moist cookies. My coworker made these first and i was sold. Just making them myself and i hope i manage to frost a few before i eat them all.
Melissa says
Lol, the struggle to wait to eat all of them is real sometimes! So happy you loved the recipe, thank you so much for leaving a review! I really appreciate it!
Mackenzie hardin says
This recipe was simple and easy to read especially since i bake alongside a 9 year old who could easily comprehend the recipe. They came out delicious!!!!!!!!!!!!!!
Diane Adams says
Just followed your instructions. Perfect. Made my grandson HAPPY!
Melissa says
So glad you guys loved this recipe! Thank you so much for taking the time to leave a review, Diane!
Mia says
These cookies are so delicious! Do you have an idea on how to make this into a cake version?!
Melissa says
Hi Mia! Funny enough I'm working on a cookie bar version of this to post this week (not quite a cake but bars). For now, though, I do have the dough recipe in bar form where you could omit the peppermint! https://www.designeatrepeat.com/thin-mint-cookie-bars/#wprm-recipe-container-35514 If you like the ganache from these cookies, you could simply 1.5x the recipe to spread on the 9x13 bars. Hope that helps!!
Lauren Smeltzer says
Is there a way to make a larger batch?
Melissa says
Yes, totally! You can scale this up to any multiple. If you're using a stand mixer a double batch is about as much as I'd do at once since the batter is thick. If you're using a hand mixer, I would just make single batches and repeat. Hope that helps!