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cosmic brownies

Homemade Cosmic Brownies

Fudgy, chewy brownies topped with a shiny chocolate ganache and colorful rainbow chips—just like the nostalgic childhood treat but better.
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Prep Time 15 minutes
Cook Time 25 minutes
Total Time 40 minutes
Servings: 16 brownies
Course: Dessert
Cuisine: American
Calories: 280
Ingredients Equipment Method Notes

Ingredients
  

  • 1/2 cup Unsalted butter Melted
  • 4 oz Semi-sweet chocolate Chopped
  • 1, cup Granulated sugar
  • 2, large Eggs Room temperature
  • 1, tsp Pure vanilla extract
  • 3/4, cup All-purpose flour
  • 1/4, cup Unsweetened cocoa powder
  • 1/2, tsp Salt
  • 2, tbsp Cornstarch The secret for chewiness!

Equipment

  • 1 8x8-inch baking pan Lined with parchment paper
  • 1 Microwave-Safe Bowl For melting butter and chocolate
  • 1 Whisk, For the batter
  • 1 Heatproof bowl For the ganache
  • 1 Offset spatula To spread the ganache evenly

Method
 

  1. Prepare: Preheat oven to 350°F (177°C). Line an 8x8-inch pan with parchment paper and spray lightly with non-stick spray.
  2. Melt: Melt butter and chopped chocolate in the microwave in 30-second intervals until smooth.
  3. Mix Wet: Whisk in sugar, then add eggs one at a time, whisking well. Stir in vanilla.
  4. Mix Dry: Whisk flour, cocoa powder, salt, and cornstarch in a separate bowl.
  5. Combine: Gently mix dry ingredients into wet until just combined. Do not overmix!
  6. Bake: Pour into pan and bake for 25-28 minutes. Edges should be set but center slightly underdone.
  7. Cool: Cool completely in the pan on a wire rack.
  8. Make Ganache: Pour hot simmering cream over chopped chocolate. Let sit for 2-3 mins, add corn syrup, and whisk until glossy.
  9. Finish: Pour ganache over cooled brownies, add rainbow chips, and refrigerate for 1 hour to set.

Notes

  • Don’t Substitute Cornstarch: This is what gives the brownies their signature dense, chewy texture.
  • Room Temp Eggs: Prevents the melted chocolate from seizing up.
  • Clean Cuts: Use a warm knife and wipe it clean between each slice for professional-looking squares.
  • Storage: Keep in an airtight container for 3 days at room temperature or 1 week in the fridge.