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.
-
Lastly, add dark cocoa powder (½ cup) and all-purpose flour (1 ¼ cups) and mix on medium until combined.
-
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
Sarah says
Holy moly! These were amazing! Even my picky teenager devoured them
Melissa says
Haha, so glad these passed the picky teen taste test! Thank you so much for taking the time to leave a review, Sarah!
Jessica says
Can I make this using dark corn syrup? My grocery store only had dark corn syrup.
Melissa says
Yes that should be just fine!
Felicity M says
im about to make this recipe and im so excited! they look so delicious, and ik they will taste so good. i also absolutely LOVE how you put the measurements in the instructions!! its so annoying when you have to keep going up to check the measurements, and ive always wondered why they dont put it in the instructions too!
Cece says
The recipe was super easy and I loved that only one bowl was used *not including the ganache bowl*. The cookie was nice and moist but held up well, it tasted like the best part of a brownie. I wish the ganache had more to it, while it tasted great and was super east I felt like it was missing something. Overall, great cookie!
Libby says
Hi Cece! When I made this recipe on my second go, I added 1/4 teaspoon of instant espresso and a pinch of salt to the ganache to give it that extra flavor. You can’t taste the espresso, it just brings out the chocolate flavor and gives it that extra depth it was missing!
Amara Donnelly says
Simple ingredients and instructions. Loved them!
Mav says
Absolutely gorgeous cookies!
Jen says
I have never been impressed by a recipe enough to leave a review but these are worth it! Super simple and quick, I didn’t have to make any modifications, and they taste amazing. I will be making again and again.
Melissa says
Yay, so glad you love this recipe and you decided to leave a review, Jen! So happy to hear you’ll be making them again! :)
Bstew says
The cookies are rich and full of chocolate flavor. Only thing I had to do different was use dark karo. The flavor is so robust. I can’t wait to share these for the holidays.
Cat says
I’m trying this tonight for santa cookies! I love all her other recipes!
Heather says
Sooo yummy!
Katie says
These look so good! Would they freeze well if I wait to add the ganache and candy?
Melissa says
Yes, freezing the cookie and waiting to decorate until after thawing would be what I would suggest!
Kirstin says
Wondering if you’ve ever frozen these cookies? I like to get a head start on my Christmas baking and always make cookies that freeze nicely!
Melissa says
You could totally freeze the unfrosted cookies and then decorate them later! I would just wait to add the ganache until after, as the ganache tends to get condensation on it when thawing.
That said, I’m going to pop some in the freezer for a few days and see how they turn out! I will add that info to the post after I test :)