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Cosmic Brownie Cookies 🍫
If cosmic brownies were the crown jewel of your childhood lunchbox, these cookies are about to make your day. They’re rich, fudgy chocolate cookies topped with silky chocolate ganache and those signature rainbow chip sprinkles, all the nostalgia in cookie form. They come together in under half an hour and taste even better than the ones from the box.
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Equipment
- Electric Hand Mixer
- Baking Sheet
- Mixing Bowl
Ingredients
For the Cookies
- 8 tbsp butter softened
- 1/2 cup light brown sugar packed
- 1/4 cup granulated sugar
- 1 egg room temperature
- 2 tbsp light corn syrup
- 1 tsp vanilla
- 1/4 tsp baking soda
- 1/4 tsp salt
- 1/2 cup cocoa powder
- 1 1/4 cups all purpose flour
For the Chocolate Ganache
- 3/4 cup chocolate chips
- 1/2 cup heavy whipping cream microwaved for 30-45 seconds until bubbling
- Sprinkles for topping
Instructions
- Preheat oven to 350 degrees. Line baking sheet with parchment paper.
- In a bowl and with an electric hand mixer on medium speed, cream together butter and both sugars (about 3 minutes).
- Add egg, vanilla, and corn syrup on low, and mix until egg is just combined (do not overmix).
- Add baking soda, salt, cocoa powder, and flour, and mix on medium until just combined.
- Shape cookies into balls and flatten to about 1/2 inch thick on parchment paper.
- Bake for 11-12 minutes.
- While baking, make the chocolate ganache by combining chocolate chips and heavy whipping cream. Let the cookies cool completely before topping each cookie with 1 tbsp of chocolate ganache and then with sprinkles. Enjoy!
Nutrition
Tips for Making This Recipe
Don’t overbake. Pull them when the tops look just set; fudgy cookies firm up as they cool, and a minute too long makes them cakey instead of dense. Let the ganache set slightly. Spoon the ganache on while the cookies are cool, then add the rainbow chips before it fully firms so they stick. Use good cocoa. Since these are all about chocolate, a rich unsweetened cocoa powder makes a real difference in flavor.
Frequently Asked Questions
What makes these taste like cosmic brownies?
The combination of a dense, fudgy chocolate cookie, a glossy chocolate ganache topping, and those signature rainbow chips is exactly what makes cosmic brownies iconic, just in cookie form.
Where do I find the rainbow chips?
The little candy-coated rainbow chips are sold as ‘rainbow chips’ or ‘rainbow sprinkles’ in the baking aisle or online. Regular rainbow sprinkles work in a pinch.
Why is corn syrup in the dough?
A little corn syrup keeps the cookies soft and chewy and gives the surface that slight sheen, just like a real cosmic brownie.
How should I store them?
Keep them in an airtight container at room temperature for up to four days. Let the ganache set fully before stacking so they don’t smudge.
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