Cosmic Brownies Recipe

They're Truly Out of This World

Cosmic Brownies

The Spruce/Bahareh Niati

Prep: 25 mins
Cook: 25 mins
Cooling Time: 45 mins
Total: 95 mins
Servings: 16
Yield: 1 (8 x 8-inch) pan
Nutrition Facts (per serving)
269 Calories
13g Fat
36g Carbs
3g Protein
Show Full Nutrition Label Hide Full Nutrition Label
Nutrition Facts
Servings: 16
Amount per serving
Calories 269
% Daily Value*
Total Fat 13g 17%
Saturated Fat 6g 30%
Cholesterol 55mg 18%
Sodium 134mg 6%
Total Carbohydrate 36g 13%
Dietary Fiber 1g 4%
Total Sugars 26g
Protein 3g
Vitamin C 0mg 0%
Calcium 17mg 1%
Iron 2mg 11%
Potassium 52mg 1%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)

Picture it. You open your lunchbox and find that Mom packed you a special treat—a brownie. But not just any brownie, a Little Debbie’s Cosmic Brownie. You peel open the cellophane package and take a bite of the dense, chewy chocolate brownie. Life is good.

Cosmic Brownies made their grand debut in September of 1999. Some say it was the day “a star was born,” and for 90s kids and Little Debbie fans across the United States it’s true—these brownies have left a lasting impression.

There are two types of people in this world: People who like fudgy brownies, and everyone else. Luckily, Cosmic Brownies have universal appeal. Why? The brownies are dense, rich, and extra chocolaty thanks to a thick layer of chocolate ganache. Oh, and there’s brightly-colored candy sprinkled on top.

Fun fact: the brownies are named after the “cosmic bowling’ craze of the 90s!

Our Secret for a Decadent, Ultra-Fudgy Brownie

The original Cosmic Brownies (you know, the packaged ones) are good, but nothing beats a homemade brownie. These brownies channel all the cosmic characteristics into a scratch-made version that will hit you in the nostalgia feels. The key to the ultra fudgy texture for this brownie is the higher fat-to-flour ratio, plus extra egg yolk and corn syrup in the batter. The result is better than the original with a richer (aka real) chocolate flavor—dare I say, it’s out of this world?

Essential Brownie-Making Tips

Cocoa powder quality matters! Because these brownies are all cocoa use a high quality powder to ensure a rich, chocolaty flavor.  

Also be careful not to overmix the batter—you want to stir just until all ingredients are combined. Over-mixing can cause these fudgy brownies to become tough. 

When spreading the brownie batter in the pan before baking, make sure the corners and edges are the same thickness as the center to ensure even baking.

For the Prettiest Cosmic Brownies, Patience Is Key

Let the brownies cool completely before topping with ganache and chill to set the ganache before slicing. For clean cut brownies: dip your knife in warm water before slicing, wipe your knife to remove any chocolate or brownie bits from the knife, and repeat the process.

“Initially, I wanted to create the exact Cosmic Brownie appearance by mail ordering rainbow coated candy but the delivery time was too long. If that's what you wish, plan ahead. Mini M&M's were a perfect substitution. The brownies are rich, fudgy and not too sweet... bite size squares of bliss.” —Mary Jo Romano

Cosmic Brownies Recipe/Tester Image
A Note From Our Recipe Tester


For the Brownies:

  • 1/4 cup vegetable oil, more for greasing the pan

  • 3/4 cup all-purpose flour, more for the pan

  • 7 tablespoons unsalted butter, melted

  • 1 cup granulated sugar

  • 1/3 cup packed light brown sugar

  • 2 large eggs, plus 1 egg yolk

  • 1 tablespoon corn syrup

  • 1 teaspoon pure vanilla extract

  • 3/4 cup unsweetened cocoa powder

  • 1/2 teaspoon salt

For the Ganache:

  • 6 tablespoons heavy cream

  • 1/2 tablespoon corn syrup

  • 1/2 teaspoon pure vanilla extract

  • Pinch salt

  • 1/2 cup finely chopped semi-sweet chocolate

  • 1/2 cup rainbow-coated candy 

Steps to Make It

Make the Brownies

  1. Gather the ingredients.

    ingredients to make cosmic brownies

    The Spruce/Bahareh Niati

  2. Position a rack in the center of the oven and heat the oven to 350 F. Grease the bottom and sides of an 8 x 8-inch baking pan with oil. Dust the pan with about 1 tablespoon flour; tilt pan and tap until the bottom and sides of the pan are coated in flour, then tap out any excess. Set the pan aside.

    oiled and floured square baking pan

    The Spruce/Bahareh Niati

  3. Whisk the melted butter, vegetable oil, and the sugars in a large bowl until well combined.

    Melted butter with brown and white sugars in a glass bowl

    The Spruce/Bahareh Niati

  4. Add the whole eggs, egg yolk, corn syrup, and vanilla. Whisk until sugar granules are dissolved and the mixture is creamy, about 5 minutes. Alternatively, use an electric hand mixer.

    cosmic brownie batter in a bowl

    The Spruce/Bahareh Niati

  5. Combine the cocoa powder, flour, and salt in a small bowl.

    cocoa powder and flour added in a glass bowl

    The Spruce/Bahareh Niati

  6. Whisk the dry mixture to the wet ingredients, until just combined and no visible streaks of dry ingredients remain.

    cosmic brownie batter in a bowl

    The Spruce/Bahareh Niati

  7. Transfer the brownie batter to the prepared baking pan. Use a butter knife or offset spatula to spread the batter into an even layer.

    brownie batter in a square baking pan

    The Spruce/Bahareh Niati

  8. Bake the brownies until the top is shiny, the brownies are set, and a toothpick inserted in the center comes out mostly clean (a few crumbs or steaks of batter is okay), 20 to 25 minutes.

    baked brownie in a square baking pan

    The Spruce/Bahareh Niati

  9. Let brownies cool in the pan for 15 minutes. Meanwhile, set a rack over a parchment-lined rimmed baking sheet.

    wire rack on a parchment covered baking sheet

    The Spruce/Bahareh Niati

  10. Run an offset spatula or butter knife around the pan to release brownies from the edges. Invert brownies onto the prepared rack and let cool completely, about 45 minutes.

    baked brownie cooling on a wire rack

    The Spruce/Bahareh Niati

Make the Ganache and Garnish

  1. Gather the ingredients.

    ingredients to make ganache

    The Spruce/Bahareh Niati

  2. Heat the cream in a medium microwave-proof bowl for 30 seconds. Add the corn syrup, vanilla, and salt. Stir to combine.

    cream in a glass bowl with vanilla

    The Spruce/Bahareh Niati

  3. Stir in the chocolate chips and let sit for 1 minute. Stir again to combine.

    chocolate in a bowl of cream

    The Spruce/Bahareh Niati

  4. Microwave the mixture in 15 to 20 second increments until the chocolate is completely melted, smooth, and shiny, stirring between each heating. Do not overcook.

    melted ganache in a glass bowl

    The Spruce/Bahareh Niati

  5. Pour the chocolate ganache over the brownies. Use an offset spatula or butter knife to spread ganache in an even layer, covering the entire top of the brownies.

    ganache covered brownie

    The Spruce/Bahareh Niati

  6. Sprinkle the brownies with rainbow-coated candy bits. Cover and refrigerate until the ganache is set. Slice into 16 brownies and enjoy.

    cosmic brownie on a wire rack

    The Spruce/Bahareh Niati


  • Corn syrup helps to keep the brownie batter fudgy and smooth by inhibiting the formation of sugar crystals during the baking process, and in the frosting makes the chocolate shinier—if you don’t have corn syrup, any inverted sugar works! Replace it with honey or golden syrups. 
  • For the ganache: If you are using milk chocolate instead of bittersweet, reduce the heavy cream to ⅓ cup (3:1 ratio). 
  • The rainbow coated candy topping is part of the iconic make-up of cosmic brownies but if you can't find them, try rainbow sprinkles, nonpareils, or mini M&M’s.


  • Store in an airtight container in the fridge for up to 7 days, or at room temperature from up to 3 days. 
  • These brownies freeze well! Wrap each brownie individually in plastic wrap, then place in an airtight container to prevent freezer burn. Freeze for up to 6 months.