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cosmic brownies

Cosmic Brownies

These cosmic brownies prove that a homemade version can genuinely beat the box without much extra effort. This cosmic brownies recipe layers a fudgy, corn syrup-enriched base with real chocolate ganache and rainbow candy, delivering everything the little debbie cosmic brownies promised without the plastic wrapper aftertaste. Whether eaten cold from the fridge or shared reluctantly at a party, this batch of homemade cosmic brownies disappears fast every single time.
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Prep Time 15 minutes
Cook Time 25 minutes
Total Time 1 hour 40 minutes
Servings: 16 servings
Course: Brownies, Dessert
Cuisine: American
Ingredients Equipment Method Notes

Ingredients
  

  • 10 tablespoons (142 grams) unsalted butter
  • 1 cup (200 grams) granulated sugar
  • 1/3 cup (67 grams) packed light brown sugar
  • 3/4 cup plus 2 tablespoons (88 grams) unsweetened cocoa powder (sifted)
  • 1/2 teaspoon vanilla extract
  • 2 large eggs plus 1 egg yolk
  • 1 tablespoon corn syrup
  • 2/3 cup (85 grams) all-purpose flour
  • 1 tablespoon cornstarch
  • 1/4 teaspoon fine sea salt
  • 1/2 cup heavy cream
  • 1 1/2 cups (255 grams) semisweet chocolate chips
  • Rainbow Candy-Coated Chocolate Chips,

Equipment

  • 8x8 metal baking pan
  • Microwave-safe bowl
  • Whisk

Method
 

  1. Preheat the oven to 350°F. Line an 8-by-8-inch metal baking pan with parchment or foil and spray with cooking spray.
  2. In a large microwave-safe bowl, melt the butter for about 90 seconds on high power. Stir in the granulated sugar, brown sugar, and cocoa powder. If still very hot, let cool slightly before adding in the vanilla, eggs, egg yolk, and corn syrup. Stir until very well combined. Add in the flour, cornstarch, and salt and stir until just combined. Batter will be thick. Pour into the prepared pan and bake for 25 minutes. Let cool completely in the pan.
  3. Place the cream in a small microwave-safe bowl and microwave on high for 1 minute. Add in the chocolate chips. Let stand for 3 minutes before stirring until smooth. Pour over the cooled brownies and smooth evenly. Sprinkle with the Rainbow Candy-Coated Chocolate Chips. Refrigerate for 1 to 2 hours, or until the frosting is set, before cutting.
  4. Brownies can be stored in an airtight container for 3 days at room temperature and for 1 week in the fridge. Brownies are best served chilled.

Recipe Notes

Corn syrup: I always include this, since that single tablespoon delivers the signature chewy bite found in the original snack cake.
Cocoa powder: I sift mine before mixing, since unsifted cocoa leaves dry pockets throughout the batter.
Chocolate chips: I use semisweet chips in the ganache, since better quality chocolate makes a noticeably better frosting.
Egg yolk: I always add the extra yolk beyond the two whole eggs, since it pushes the texture toward maximum fudginess.
Rainbow candies: I use the classic flat candy-coated chips, though mini M&Ms work as a reliable substitute.