Cosmic Brownies are a fun and delicious treat that brings a little bit of nostalgia to anyone who remembers the classic snack from childhood. These brownies are rich, fudgy, and topped with a smooth chocolate ganache and colorful rainbow candy-coated chocolate chips. Perfect for parties, picnics, or just a cozy night in, this recipe will surely satisfy your sweet tooth!

Why Make This Recipe
Making Cosmic Brownies at home is easy and rewarding! You can enjoy these delightful treats fresh from the oven, allowing you to control the ingredients and customize them to your liking. Whether you’re baking for yourself or sharing with friends and family, these brownies are sure to bring smiles and joy. Plus, they are simple enough for even beginner bakers to make!
How to Make Cosmic Brownies
Ingredients:
- ¾ cup all-purpose flour (90 grams; for gluten-free, use a 1-1 flour)
- ⅔ cup unsweetened cocoa powder (56 grams)
- 12 tablespoons unsalted butter (170 grams, melted; 1½ sticks; salted works too; if using salted butter, omit the kosher salt)
- 1 cup granulated sugar (200 grams; or use brown sugar)
- ½ cup brown sugar (107 grams)
- 2 large eggs (50 grams, room temperature)
- 1 teaspoon pure vanilla extract (4 grams)
- ¾ teaspoon kosher salt
- 1 cup chocolate chips (170 grams; milk, semisweet, or dark chocolate chips all work)
- ½ cup heavy cream (114 grams)
- ¼ cup rainbow candy-coated chocolate chips (43 grams; for topping; use mini M&M’s or rainbow sprinkles instead)
Directions:
- Preheat the oven to 325°F (160°C). Spray a 9×9-inch baking pan with nonstick spray and line it with parchment paper. Set aside.
- In a medium bowl, whisk together the flour and cocoa powder.
- In a separate larger bowl, whisk the melted butter and both sugars together.
- Add the eggs, vanilla extract, and salt to the butter and sugar mixture. Mix well.
- Gradually add the flour mixture into the wet ingredients. Stir until just combined. Be careful not to overmix, or your brownies may turn out tough.
- Pour the brownie batter into the prepared pan and use a spatula to spread it evenly.
- Bake for 30-35 minutes, or until a toothpick inserted comes out nearly clean. Allow the brownies to cool.
- While the brownies are baking, heat ½ cup of heavy cream in a pot and add 1 cup of chocolate chips. Stir until the chocolate melts and the mixture is smooth.
- Spread the chocolate ganache over the cooled brownies. Sprinkle rainbow chips on top.
- Refrigerate or freeze until the frosting sets before enjoying!
How to Serve Cosmic Brownies
Serve Cosmic Brownies at room temperature or chilled, cut into squares. They are perfect for parties, lunchboxes, or as a delightful dessert after dinner. Pair them with a scoop of ice cream for an extra special treat!
How to Store Cosmic Brownies
Store leftover Cosmic Brownies in an airtight container at room temperature for up to 3 days. For longer storage, refrigerate them for up to a week or freeze them for up to three months. Just make sure to wrap them well to prevent freezer burn!
Tips to Make Cosmic Brownies
- Don’t overmix the batter to ensure your brownies stay soft and fudgy.
- Allow the brownies to cool completely before adding the ganache for the best texture.
- Experiment with different types of chips or toppings to customize your brownies.
Variation
Try adding nuts, such as walnuts or pecans, for a crunchy texture, or use flavored chocolate chips, like peanut butter or mint, for a fun twist.
FAQs
Q: Can I make these brownies gluten-free?
A: Yes! Simply use a gluten-free 1-1 flour in place of the all-purpose flour to make them gluten-free.
Q: How can I make the brownies more chocolatey?
A: You can add more cocoa powder or use chocolate chips mixed into the batter for an extra chocolate boost.
Q: Can I use oil instead of butter?
A: While butter provides a rich flavor, you can substitute it with an equal amount of vegetable oil for a different texture.
Enjoy your homemade Cosmic Brownies! They’re sure to be a hit with everyone.

Cosmic Brownies
Ingredients
Brownie Batter
- ¾ cup all-purpose flour (90 grams; for gluten-free, use a 1-1 flour) Use gluten-free flour if needed.
- ⅔ cup unsweetened cocoa powder (56 grams)
- 12 tablespoons unsalted butter (170 grams, melted; 1½ sticks; salted works too) If using salted butter, omit the kosher salt.
- 1 cup granulated sugar (200 grams; or use brown sugar)
- ½ cup brown sugar (107 grams)
- 2 large eggs (50 grams, room temperature)
- 1 teaspoon pure vanilla extract (4 grams)
- ¾ teaspoon kosher salt
Chocolate Ganache Topping
- 1 cup chocolate chips (170 grams; milk, semisweet, or dark chocolate chips all work)
- ½ cup heavy cream (114 grams)
Toppings
- ¼ cup rainbow candy-coated chocolate chips (43 grams; for topping) Can substitute with mini M&Ms or rainbow sprinkles.
Instructions
Preparation
- Preheat the oven to 325°F (160°C). Spray a 9×9-inch baking pan with nonstick spray and line it with parchment paper. Set aside.
- In a medium bowl, whisk together the flour and cocoa powder.
- In a separate larger bowl, whisk the melted butter and both sugars together.
- Add the eggs, vanilla extract, and salt to the butter and sugar mixture. Mix well.
- Gradually add the flour mixture into the wet ingredients. Stir until just combined, being careful not to overmix.
- Pour the brownie batter into the prepared pan and use a spatula to spread it evenly.
Baking
- Bake for 30-35 minutes, or until a toothpick inserted comes out nearly clean. Allow the brownies to cool.
- While the brownies are baking, heat ½ cup of heavy cream in a pot and add 1 cup of chocolate chips. Stir until the chocolate melts and the mixture is smooth.
- Spread the chocolate ganache over the cooled brownies. Sprinkle rainbow chips on top.
- Refrigerate or freeze until the frosting sets before enjoying!







