These TikTok viral copycat Cosmic Brownies are rich, thick and fudgy brownies topped with a smooth chocolate ganache and those cosmic candy coated chocolate bits. They are just as chocolatey and fudgy as store bought, but fresher and more flavorful since they're homemade.
Cosmic Brownies are fabulous any time of the year. This recipe uses brown sugar, corn starch and an extra egg yolk to make them thicker and fudgier like the Little Debbie Cosmic Brownies. Use your extra egg white to make our Egg White Granola. We tested these repeatedly for the perfect flavor and felt like to stay true to the flavor of the real Cosmic Brownies
This was inspired by our Peppermint Brownies on this site, and pairs well with this Brownie Oreo Trifle.
For another fun and nolstalgic treat that kids and adults will love, try these Dinosaur Cupcakes!
Jump to:
Ingredients
Below is a list of ingredients needed for this recipe. Follow our tips on each ingredient for best results.
- butter- I used unsalted. If all you have is salted, decrease salt by ¼ teaspoon
- brown sugar - I recommend light brown sugar with this recipe, we tested it with dark and it added a richness that we didn't prefer for this recipe.
- granulated white sugar
- vanilla- we always recommend using pure vanilla, but we found while testing this recipe imitation is fine as vanilla isn't the highlighted flavor. Our taste testers couldn't tell a difference.
- eggs- large
- flour - regular all-purpose flour
- cocoa powder - make sure it's unsweetened
- corn starch - gives it that extra chewiness that we love
- salt
- whipping cream - I used heavy, but regular would also work
- milk and dark chocolate chips - we tested the ganache over and over to get the flavor to match up to Little Debbies and found that both dark and milk chocolate chips created the best flavor.
See recipe card for quantities.
How to Make Homemade Cosmic Brownies
Use these process shots to help get the results you are wanting. The pictures can help with texture and be a visual guide for best results.
For the Batter:
1. Preheat oven to 350*F. Melt butter in the microwave then whisk together in a microwave safe bowl with the sugar until well combined. Place in the microwave for 45 seconds and whisk lightly. Let sit for 2 minutes. Microwave an additional 30 seconds and whisk. The mixture should be smooth and the sugars should be dissolved. Microwave an additional 30 seconds if necessary.
2. Add 2 whole eggs + one egg yolk to the butters and sugar. Whisk vigorously until silky and smooth. About 40-90 seconds depending how vigorously you whisk. You'll know when you're done because it will look nice and smooth.
3. Add the dry ingredients to the batter. Using a spatula and a folding motion, combine the dry ingredients and the wet ingredients. Check out this video for more information on how to fold, if necessary. Fold only until no white specks remain.
4. Place in a greased 8x8 baking dish. I like to add parchment paper to the bottom for easier removal, but you don't have to. Bake for 24-30 minutes. The top will start to get that crackly top and a toothpick should come out clean. Allow to cool completely. You can speed up the cooling by placing it in the refrigerator after it has cooled on the counter at least 45 minutes first.
For the Ganache:
5. Once the brownies are completely cooled, make the ganache. Measure semi-sweet and milk chocolate chips into a glass bowl. Microwave whipping cream in a microwave safe bowl until hot and bubbly, about 60 seconds. Pour on top of chocolate chips and allow to sit for 30-60 seconds then whisk until smooth.
6. Allow the ganache to cool for a couple of minutes then pour on top of the cooled brownies. Spread it smooth and allow set aside until cooled. Once they are cooled to room temperature, sprinkle the rainbow coated chocolate chips on top and dig in! We recommend using a plastic knife to cut brownies, but a metal knife will work too.
Hint: Don't over bake the brownies! They will be dry and crumbly. For fudgy, moist brownies, remove from oven as soon as they are done! An inserted toothpick should come out either clean or it might have a little bit of moist crumbs on it. If there is wet batter on the toothpick, they need more time.
Substitutions and Variations
We love switching things up when we're in the kitchen. Try any of these variations for something a little different.
- M&M's - use mini M&M's instead of rainbow coated chocolate chips. They taste almost the same and are a lot less expensive.
- Icing- you can make these with an icing instead of ganache, if desired. Simply use your favorite chocolate icing recipe to use instead.
- Milk Chocolate - these brownies are pretty rich and a little dark. If you prefer something milkier use only milk chocolate chips in the ganache and exchange 2 Tablespoons of the cocoa powder for 2 Tablespoons of flour.
- Extra Dark - For extra dark brownies, use only semi-sweet chocolate chips in the ganache and exchange 2 Tablespoons of flour for 2 more Tablespoons of cocoa powder.
- Cosmic Brownie Ice Cream- get your favorite chocolate ice cream, chop some of these up to put on top, then top with your favorite chocolate sauce and more rainbow candy coated chocolate chips.
How to Serve Cosmic Brownies
These are fun to take to a party or gathering of some sort. My kids love them as a special treat. We love to serve them with a scoop of ice cream and make them into Cosmic Brownie Sundaes with whipped cream and toppings.
Storage
Store in an airtight container at room temperature or in the refrigerator for up to 3 days. They will last longer before going bad, but we recommend eating them sooner to maintain the amazing texture!
Store fresh brownies in the freezer in an airtight container for up to 2 months. We recommend only thawing them when you are ready to eat them. Allow to thaw at room temperature for about 1 hour, then eat immediately or they will start to weep.
Top tips
Don't skip cooling the brownies! Pouring hot ganache on hot brownies could make the ganache absorb into the brownies changing the texture.
Do not over bake these brownies or they will be dry and crumbly instead of moist and fudgy. An inserted toothpick should come out clean or have a few moist crumbs on it.
Recipe
Cosmic Brownies
Ingredients
For the Brownies:
- 10 Tablespoons unsalted butter
- ¾ cup granulated sugar
- ⅔ cup brown sugar
- 2 teaspoons vanilla
- 2 whole eggs plus 1 egg yolk
- ¾ cup cocoa powder
- ¾ cup all purpose flour
- 1 Tablespoon corn starch
- ½ teaspoon salt
For the Ganache:
- we tested the ganache and found using half milk chocolate chips and half semi sweet chocolate chips was more true to the real taste
- ½ cup heavy whipping cream
- ¾ cup milk chocolate chips
- ¾ cup semi-sweet chocolate chips
- Rainbow candy coated chocolate chips or mini M&M's
Instructions
For the brownies:
- Preheat the oven to 350*F.
- Melt butter and place in a microwave safe bowl with the sugar and brown sugar. Whisk to combine. Put in the microwave in 30 second intervals, whisking between each one until smooth. The goal is to dissolve the sugars and end up with a smooth consistency. This should take no more than 3 times of being in the microwave for a total of 90 seconds.
- Add the vanilla, eggs and egg yolk and whisk vigorously until silky and smooth, about a minute.
- Add the cocoa powder, flour, corn starch and salt and fold into the wet ingredients just until the white specks of flour disappear. Don't over mix!
- Pour batter into a greased 8x8 baking dish and bake in a 350*F preheated oven for 24-30 minutes. The top will be crackly and an inserted toothpick should come out clean.
- Allow to cool on the counter for at least 30 minutes, then cool in the refrigerator another 1-2 hours. Or, cool on the counter 3+ hours.
For the ganache:
- Measure milk chocolate chips and semi-sweet chocolate chips into a heat safe bowl.
- Place heavy whipping cream in a heat safe bowl and microwave until hot and bubbly, 60 seconds.
- Pour whipping cream on top of chocolate chips and allow to sit for 30-60 seconds. Whisk until smooth.
- Pour ganache over top of the cooled brownies and spread smooth.
- Allow to cool an additional 30 minutes in the refrigerator or 1 hour on the counter.
- Top with rainbow coated chips and enjoy!!
Notes
- Store in an airtight container in the refrigerator or at room temperature for up to 3 days.
- Store fresh brownies in an airtight container in the freezer for up to 2 months. Thaw by leaving at room temperature for 1-2 hours then eat immediately.
- Make sure your butter and sugar mixture is nice and smooth before moving on to the next step.
- Make sure not to over bake or you will have dry, crumbly brownies. For authentic, rich fudgy brownies, make sure to remove from oven as soon as in inserted toothpick comes out clean or has moist crumbs on it.
- Allow the brownies to cool completely before adding the ganache. Otherwise the ganache will absorb into the brownies making them into something other than a cosmic brownie.
- We love to serve these with ice cream and whipped cream for a fun sundae!
Nicole says
I saw these on tiktok and these cosmic brownies were really fun to make homemade. We love a good copycat recipe and Little Debbie treats are so fun. I decided to cut them into rectangles and make them with the line on them like the old ones. My kids loved them! Excited to try them with ice cream next time! Great recipe!! They were really rich and fudgy!
Katherine says
These brownies are so fun! Perfect for my daughter's party. Yum!
Jacob says
We loved making these Cosmic Brownies at home. Great recipe. So good.
Ava M. says
Oh my gosh we love these so much, I've made them twice since the first time in June. I saw them on tiktok and had to make them. I love brownies and these were a nice way to spend a summer afternoon with the kids 🙂