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.
Carmelina Bruno says
Itโs so easy to make.. I love that you have the measurements in the instruction so I donโt have to scroll up!! LOVE IT and itโs DELICIOUS!!
Melissa says
Thank you so much for taking the time to leave a review, Carmelina! I really appreciate it!
Rebekah Mann says
Iโm excited to make this recipe, but have a friend who is gluten free and nut free. What would be the best flour to use to make this gluten and nut free without changing the texture much?
Melissa says
Hi! I haven't specifically tested this one GF but Bob's Red Mill 1-to-1 swap flour is the one I use. I suspect you will need to use more flour, though, since it doesn't absorb as well. I'd suggest baking 1 cookie first and then if it totally spreads, add more flour to the dough. Gluten-free baking isn't my forte but that flour usually works well as a sub!
Carrie Hicks says
Looooove. I had a hard time with the ganache, but that was a user error.
Definitely making these again and again and again
Melissa says
So glad you loved them, Carrie! Ganache can be a little finicky sometimes but I'm glad they still turned out!
Abigail L says
This recipe was a big hit with all my friends and family. I would definitely use this recipe again. The cookies turned out just like I imagined them!
Melissa says
SO glad to hear everyone loved this recipe, Abigail! Thank you so much for taking the time to leave a review!
Tori says
OMG dangerously delicious. Anytime I want something chocolatey, this will be my go-to! Obsessed 10/10
Melissa says
YAY, so glad you love this recipe, Tori! Thank you so much for leaving a review!
Meg says
Hi there! I tried this recipe but made gluten friendly I swapped out the suggested for bobs red mill 1-1 gf flour baking flour however they turned out super wet and spread everywhere I had to cookie scoop and they were really sticky I couldnโt roll them into a ball, I tried a second batch of batter thinking maybe i miss measured but the batter turned out the same, it looks like a brownie dough nothing like a cookie dough I scooped I popped this batch in the freezer to see if I can maybe roll them and they can keep their shape but itโs not looking promising, is there something Iโm doing wrong? Or a suggestion how to fix this ?
Melissa says
Hi Meg! What kind of butter are you using?
Gabby Fink says
Wanted something to make tonight that was relaxing, but unique. Such a fun idea and I had everything besides sprinkles already in my pantry/fridge. Definitely recommend if you are looking for something in between a cookie and a brownie!
Melissa says
Thank you so much for leaving a review, Gabby! So glad you loved the recipe!
Mrs S says
Terrific recipe, loved by family!
I didnโt have heavy cream so I used 4 Tbsp butter and a little vanilla and a pinch of salt. Melted together in microwave, stirred until thickened and applied to cooled cookies
Melissa says
Awesome to hear they turned out without having the heavy cream on hand! Thank you so much for taking the time to leave a review!
Matthew Daniel says
These cookies are soo delicious!! I would recommend having milk on hand, because they are very rich๐๐
Melissa says
Thank you so much for leaving a review, Matthew! I really appreciate it!
Lisa says
Super easy and so good!! I have never made ganache, but it turned out perfectly.
Melissa says
That's awesome to hear! Thank you so much for taking the time to leave a review, Lisa!
Jess Heinzen says
Made these for my VERY picky husband for Fatherโs Day and he LOVED them. They are so much better chilled too! I will definitely be making these again.
Melissa says
YAY, always glad to hear when one of my recipes passes a picky eater's taste teste! :) Thank you so much for leaving a review, Jess!
Natalie says
I literally never bake because iโve been known to mess up simple box cakes, but I made these and they turned out amazing!! I had quite a bit of left over ganache (maybe I wasnโt generous enough with it on the cookies lol), but it wasnโt a issue at all. These were so easy and super delicious!!
Melissa says
Lol, so glad they ended up turning out for you, Natalie! Thank you so much for trying out the recipe and taking the time to leave a review!
Lily Barrentine says
Delicious!!! I made these and they turned out perfect.
Melissa says
Thank you so much for leaving a review, Lily! :)
Kendra Johnson says
You need to be more famous!! I canโt wait to bake these cosmic brownies cookies. I found your tiktok sand I found numerous more recipes that I want to try. They all look so delicious and Are all so pleasing to the eye. The videos are filled with helpful tips and baking hacks. Love your stuff!
Melissa says
LOL thank you so much for such a kind review, Kendra! Let me know what recipes you end up trying out! :)
Jenna says
Fantastic! I've made these a few times now and they have been a hit every time! I didn't have corn syrup on hand, but I replaced it 1 to 1 with maple syrup and it tastes great. Good consistency too!
Melissa says
Great to hear everyone loves this recipe, Jenna! And I'm so glad it worked with your substitution! Thank you so much for leaving a review!
Kristin says
Hi! Are there any recommendations you would make (temp or time wise) if I wanted to make them half the size to make 16 cookies? Iโm the home baker of a fairly large office, so 8 cookies per batch would take so much! Thank you!!
Melissa says
Yes! You can roll (and still flatten) into 1 tablespoon balls and bake for 8-9 minutes or do 2 tablespoon balls and do 9-10 minutes! Still keep the temperature at 350F.