The BEST soft, fudgy, and chewy brownie cookies inspired by Little Debbie’s cosmic brownies! Enjoy chilled for the perfectly fudgy & dense texture.

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.
Make it gluten-free! Use your favorite gluten-free flour to make this gluten-free! My favorite brand is Bob’s Red Mill Gluten Free 1-to-1 Baking Flour.

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 350°F.
- In a large bowl, use an electric mixer on medium-high speed to cream softened unsalted butter (½ cup, 1 stick), light brown sugar(½ cup), and granulated sugar (¼ 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 (¼ teaspoon) and salt (¼ teaspoon) and mix for another 5-10 seconds until combined.
- Lastly, add dark cocoa powder (½ cup) and all-purpose flour (1 ¼ 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 1/4 cup (4 tablespoons) sized scoops (I use this stainless steel cookie scoop!), roll into balls, then gently flatten each dough ball into a 1/2″ thick disc; this will help them spread instead of be puffy. Bake at 350°F 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:
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.
I tested this recipe over 5 times and you just can’t achieve the dense, fudgy texture without a tiny bit of corn syrup. In addition, the corn syrup adds sweetness to the cookie without adding more granulated sugar which can give it a gritty texture. I promise it’s worth it!
If you don’t want to use it or 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.
You can, just keep in mind that you won’t have as moist, rich, and fudgy of a cookie. Regular unsweetened cocoa powder is more acidic and will react with the baking soda, creating a puffier cookie.
To get the ultimate chewy, fudgy texture…yes! I highly recommend chilling these both before serving & for storing. The rule of thumb for ganache is that you can keep it at room temperature for up to 2 days but I like to keep them refrigerated to be safe.
Did you make this recipe? If so, 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.
Fudgy Cosmic Brownie Cookies (TikTok Viral!)
The BEST soft, fudgy, and chewy brownie cookies inspired by Little Debbie's cosmic brownies! Enjoy chilled for the perfectly fudgy & dense texture.

Ingredients
- ½ cup unsalted butter softened
- ½ cup light brown sugar
- ¼ 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!
- ¼ teaspoon baking soda
- ¼ teaspoon salt
- ½ cup dark cocoa powder I use Hershey's Special Dark
- 1 ¼ cup all-purpose flour
Toppings:
- ¾ cup semi-sweet chocolate chips
- ¼ 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 350°F.
-
In a large bowl, use an electric mixer on medium-high speed to cream softened unsalted butter (½ cup, 1 stick), light brown sugar (½ cup), and granulated sugar (¼ 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 (¼ teaspoon) and salt (¼ teaspoon) and mix for another 5-10 seconds until combined.
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Lastly, add dark cocoa powder (½ cup) and all-purpose flour (1 ¼ cups) and mix on medium until combined.
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Scoop dough into 1/4 cup (4 tablespoons) sized scoops (I use this stainless steel cookie scoop!), roll into balls, then gently flatten each dough ball into a 1/2" thick disc; this will help them spread instead of be puffy.
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Bake at 350°F 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:
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In a medium-sized, heat-safe bowl (cereal bowl sized), place semi-sweet chocolate chips (¾ cup).
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In a separate medium-sized bowl or large liquid measuring cup, heat heavy cream (¼ cup) in the microwave for 30-45 seconds, or until it begins to bubble (it’s important that your measuring cup or bowl is at least 4x 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.
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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:
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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.
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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.
Recipe 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.
Nutrition information is calculated using an ingredient database and should be considered an estimate
Ellie says
Loved! So delicious and easy!
Merissa says
Made these for coworkers, they loved them. Easy to make and look like a bakery cookie with out much effort on your part. Will be making them again.
Melissa says
Yay, so glad to hear everyone enjoyed this recipe! Thank you so much for taking the time to leave a review, Merissa!
Julie wild says
I don’t know what I did wrong my cookies expanded really big. 😕 guess off to try again. I love how it tastes even though their big lol 😆
Melissa says
Hi Julie! Did they expand upwards (like puffy) or spread out? Puffy can be if you happened to use regular cocoa powder vs. dark (regular is more acidic so it will react more to the baking soda). If they spread, it could be the brand of butter you used (was it real butter vs. margarine), under measuring the flour, or if your oven bakes cool then they can spread more than you want.
Hope that helps! Would love to help you troubleshoot more, if needed!
Gail says
They are the perfect mix of chewy and fudgey. I made them for my family and they absolutely adore them. They maybe lasted a day before they were all eaten, so naturally I had to make more. This recipe really is 5/5 for me.
Melissa says
Ahhh yay, so glad to hear you and the family enjoyed these cookies so much! Thank you so much for taking the time to leave a review, Gail!
Sara says
Made these for a work party and they got RAVE reviews!
Melissa says
So glad to hear everyone loved this recipe, Sara! Thank you so much for leaving a review!
Jordan says
I made these for my husband/associates at my store. They LOVED them. They all immediately begged me for more so I made 5 batches in the span of 4 days
Melissa says
Wow, you’ve been busy!! Sooo happy to hear everyone loved these so much! Thank you so much for taking the time to leave a review, Jordan! :)
Phineas says
AMAZING! A must bake. Fun to bake with kids who won’t mind their sticky hands. My husband and I had to put them away so we would stop eating them.
Melissa says
LOL, they are definitely hard to resist not eating them all at once! I’m so glad to hear you and your family enjoyed this recipe! Thank you so much for leaving a review! :)
Kristyn Waits says
LOVE AND SOO EASY TO MAKE!
Lisa says
This looks amazing! I have dark corn syrup on hand, wondering how that would change the cookie? Also, do you think this base could be used with mix-ins such as Andes mint chips?
Melissa says
I think dark syrup would be fine! And yes, bring on those mix-ins! I actually made a sample cookie with Andes mint chips and it was so good!
Hailey says
These are amazing. I doubled the recipe and it made a perfect bakers dozen! At first my mixer and I were worried when I added the dry ingredients – it seemed like it was too thick and dry, but we held on tight a minute more and suddenly the dough became the perfect play dough consistency. Super easy to shape and not sticky at all. Thank you Melissa!
Melissa says
Haha, it is a pretty thick dough so I’m glad you persisted and they ended up turning out for you with the double batch! Thank you so much for leaving a review, Hailey!