Homemade Cosmic Brownies

Name: Homemade Cosmic Brownies
Prep time: 15 min
Cook time: 25 min
Total time: 40 min
Yield: 9
Cuisine: American
Ingredients: 1/2 cup unsalted butter, melted; 1 cup granulated sugar; 2 large eggs; 1 teaspoon vanilla extract; 1/3 cup cocoa powder; 1/2 cup all purpose flour; 1/4 teaspoon salt; 1/4 teaspoon baking powder; 1/2 cup semi sweet chocolate chips; 3 tablespoons heavy cream; 1/4 cup rainbow chip sprinkles

These thick and chewy brownies topped with rich chocolate ganache and rainbow chips are just like the ones you remember from your childhood.

By Recipes By Nani· 🌍 American· July 18, 2026

recipesbynani.com

Prep

15 minutes

Cook

25 minutes

Total

40 minutes

Serves

There is something so special about the classic Cosmic Brownie. These bars are incredibly fudgy, dense, and topped with a smooth layer of chocolate frosting that sets perfectly. They are the ultimate treat to pack in a lunch or share at a party because everyone loves that nostalgic pop of rainbow color on top.

My best tip for getting that signature texture is to avoid overbaking the brownies. You want to take them out of the oven when a toothpick comes out with just a few moist crumbs attached. If you leave them in too long, they lose that fudgy quality that makes them so delicious.

🧺 Ingredients

1/2 cup unsalted butter, melted
1 cup granulated sugar
2 large eggs
1 teaspoon vanilla extract
1/3 cup cocoa powder
1/2 cup all purpose flour
1/4 teaspoon salt
1/4 teaspoon baking powder
1/2 cup semi sweet chocolate chips
3 tablespoons heavy cream
1/4 cup rainbow chip sprinkles

👩‍🍳Instructions

1
Preheat your oven to 350 degrees Fahrenheit and grease an 8 by 8 inch baking pan.
2
In a large bowl, whisk together the melted butter and sugar until smooth.
3
Beat in the eggs and vanilla extract until the mixture is well combined.
4
Stir in the cocoa powder, flour, salt, and baking powder until the batter is just mixed.
5
Pour the batter into your prepared pan and bake for 20 to 25 minutes.
6
Let the brownies cool completely in the pan.
7
For the ganache, melt the chocolate chips and heavy cream together in the microwave in 30 second intervals, stirring until smooth.
8
Spread the ganache evenly over the cooled brownies and top immediately with the rainbow chips.
9
Allow the frosting to set before slicing into squares.

💡 Tips

Store these brownies in an airtight container at room temperature for up to three days. If you want them to last longer, you can keep them in the fridge for a week. They taste wonderful chilled, especially on a warm day.

#dessert #chocolate #homemade #easy recipe #sweets

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