Warm and fuzzy feelings of nostalgia will come flooding back as you bite into an improved version of Cosmic Brownies! Homemade with no artificial or cloyingly sweet flavors, these brownies are definitely better than store-bought with rich, fudgy notes throughout.
Preheat the oven to 350F. Line an 8 by 8-inch baking pan with 2 pieces of parchment paper so it hangs over all 4 sides for easy removal.
Whisk together the flour, cocoa powder, and salt in a medium bowl.
Use a handheld electric mixer to beat together the granulated sugar, brown sugar, oil, butter, and vanilla in a large bowl until it thickens slightly, and looks like fluffy wet sand. Add the eggs and egg yolk, and beat until the mixture is thick, fluffy, and turns paler (about 6 to 8 minutes using a handheld electric mixer).
Add the dry ingredients and beat just to combine, being careful not to over-mix.
Pour the batter into the prepared pan, and spread it out evenly.
Bake until the brownies are set along the outside and the top starts to crackle, about 20 to 25 minutes, being careful not to over-bake. Cool completely.
Making the Ganache
Once the brownies are cooled, make the ganache. Add the chocolate chips and cream to a large bowl, microwave for 45 seconds, let it sit for 30 seconds, and then gently stir. Microwave in additional 10-second intervals until the chocolate is fully melted, stirring gently between each interval. Alternatively, you can use a double boiler instead of the microwave.
Assembling the Brownies
Once the brownies are fully cooled, spread the ganache on top, and then add the rainbow chip sprinkles.
Let the ganache set before cutting and serving.
Notes
For an extra shiny ganache, add 1/2 tablespoon corn syrup along with the chocolate chips and heavy whipping cream.
***For best results, make sure to let the brownies cool completely before you spread on the ganache, and then let the ganache set fully before cutting.
The toothpick test doesn’t work great to test for doneness because brownies will still be a touch gooey when they’re finished (they will set as they cool). And they’re actually a bit overcooked if the toothpick comes out clean! Instead, you can tell when the brownies are finished because they’ll be set along the outside, crackled on top, and puffed (the puff will go down as they cool).
For Slicing - To create clean slices, run your knife under hot water and wipe off the fudgy bits (then run under hot water again) before each slice.
Storage - To keep the texture of the ganache closest to that of a cosmic brownie, it's recommended to keep them stored in the refrigerator. Store the homemade cosmic brownies covered tightly with plastic wrap or in an air-tight container kept in the refrigerator for up to 6 days.
To Freeze - First, flash freeze the brownies on a baking sheet until firm to the touch. Then, individually wrap the brownies in plastic wrap and place them in a large ziptop bag or air-tight container in the freezer for up to 2 months. Unwrap and thaw at room temperature or overnight in the refrigerator.