My childhood favorite treat is of course the original Cosmic Brownies, so of course we needed to make these Copycat Cosmic Brownies for all of the Little Debbie Cosmic Brownies lovers.
Now with these homemade cosmic brownies, you can avoid going to the grocery store and make this homemade version and all the mini M&M pieces you want and are great for school lunches!
If on the off chance, you haven’t ever tried Little Debbie brownies snack cakes, they have the best fudgy texture with a melted chocolate ganache frosting on top of the brownies with rainbow chips.

Ingredients used to make Copycat Cosmic Brownies:
For the brownies
- Butter, melted
- Vegetable oil
- Granulated sugar
- Brown sugar
- Unsweetened cocoa powder
- Vanilla extract
- Egg and extra egg yolk
- Corn syrup
- All purpose flour
- Cornstarch
- Salt
For the ganache
- Heavy cream
- Semi-sweet chocolate chips
- Light corn syrup
- Rainbow sprinkles (or rainbow chip sprinkles)
Equipment Needed
For this recipe, you only need a few simple kitchen tools. We recommend using the following equipment:



How to make Copycat Cosmic Brownies
- Prep. Preheat the oven to 350°F and line an 8X8-inch baking pan with parchment paper. Make sure to leave a bit of parchment paper hanging over the sides of the pan.
- Make the brownie batter. Whisk together the butter, vegetable oil, sugars, cocoa powder, vanilla, egg, egg yolks, and corn syrup until smooth. Whisk in the flour, cornstarch, and salt until smooth.
- Bake. Pour the batter into the prepared pan and bake for 20-25 minutes or until a toothpick inserted in the center comes out mostly clean.
- Cool. Remove the brownies from the oven and allow them to cool completely in the pan.
- Make the ganache. While the brownies are cooling, heat the heavy cream until it’s almost boiling and pour it over the chocolate chips. Let the mixture sit for a couple of minutes before whisking it until smooth. Whisk in the corn syrup.
- Frost the brownies. Use the parchment paper to lift the fully cooled brownies from the pan. Spread the ganache over the brownies and top with rainbow sprinkles.



Storage Suggestions
If you manage to have any leftover Bars + Brownies, these can store well if prepped appropriately. Once they have cooled completely, here is how you can store it:
- Counter: Store bars and brownies in an airtight container at room temperature for up to 4 days. If your kitchen is particularly warm, consider refrigerating instead to prevent them from getting too soft or melty.
- Refrigerator: Place in an airtight container and refrigerate for up to 1 week. Let them come to room temperature before serving for the best texture and flavor.
- Freezer: To freeze, make sure bars and brownies are completely cooled and unfrosted. Wrap tightly in plastic wrap (or Press & Seal) and then place in a freezer-safe bag or container. For easier portioning, wrap individual squares before freezing. Don’t forget to label with the date. They’ll stay fresh in the freezer for up to 3 months.
Ways to add to this homemade brownies copycat recipe:
One of the best things about making this homemade cosmic brownie recipe is that you can make the fudgy cosmic brownies anything you want them to be and better than any packaged brownies you get from the grocery store. Here are a few ideas:
- Add chocolate chips to the brownie batter
- Use chocolate frosting instead of the chocolate ganache
- Top the brownies with mini m&m instead of colorful sprinkles
Enjoy More Delicious Brownies Recipes
There’s nothing better than an easy brownie or bar recipe. Check out our comprehensive list of brownies, bars, and blondies here.

Copycat Cosmic Brownies Recipe
Ingredients
Brownies
- 8 Tablespoons butter, melted
- 2 Tablespoons vegetable oil
- ⅔ cup granulated sugar
- ⅔ cup brown sugar
- ¾ cup unsweetened cocoa powder
- 1 teaspoon vanilla extract
- 1 egg
- 3 egg yolks
- 1 ½ Tablespoons corn syrup
- ⅔ cup all-purpose flour
- 1 Tablespoon cornstarch
- pinch of salt
Ganache
- ½ cup heavy cream
- 1 ½ cups semi sweet chocolate chips
- 1 Tablespoon light corn syrup
- ½ cup rainbow sprinkles
Instructions
- Prep. Preheat the oven to 350°F and line an 8X8-inch baking pan with parchment paper. Make sure to leave a bit of parchment paper hanging over the sides of the pan.
- Make the brownie batter. Whisk together the butter, vegetable oil, sugars, cocoa powder, vanilla, egg, egg yolks, and corn syrup until smooth. Whisk in the flour, cornstarch, and salt until smooth.
- Bake. Pour the batter into the prepared pan and bake for 20-25 minutes or until a toothpick inserted in the center comes out mostly clean.
- Cool. Remove the brownies from the oven and allow them to cool completely in the pan.
- Make the ganache. While the brownies are cooling, heat the heavy cream until it’s almost boiling and pour it over the chocolate chips. Let the mixture sit for a couple of minutes before whisking it until smooth. Whisk in the corn syrup.
- Frost the brownies. Use the parchment paper to lift the fully cooled brownies from the pan. Spread the ganache over the brownies and top with rainbow sprinkles.
Notes
- Add chocolate chips to the brownie batter
- Use chocolate frosting instead of the chocolate ganache
- Top the brownies with mini m&m instead of colorful sprinkles



















This recipe was delish!