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Close-up of rich, fudgy chocolate brownie cookies topped with glossy chocolate frosting and colorful cosmic sprinkles, cooling on a wire rack – perfect fudgy cosmic brownie recipe.

Chewy Cosmic Brownie Cookies

Indulge in these rich, fudgy brownie-inspired cookies topped with rainbow sprinkles for a playful twist on a classic treat.
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Prep Time 15 minutes
Cook Time 12 minutes
Chill Time 1 hour
Total Time 1 hour 27 minutes
Servings: 8
Course: Dessert, Snack
Cuisine: American, Baking
Calories: 410
Ingredients Equipment Method Nutrition Notes

Ingredients
  

  • ½ cup unsalted butter softened to room temperature for easy creaming
  • ½ cup light brown sugar packed for even sweetness
  • ¼ cup granulated sugar regular white sugar
  • 1 large egg room temperature to prevent curdling
  • 1 teaspoon vanilla extract pure for deep flavor
  • 2 tablespoons light corn syrup adds chewiness, not high fructose
  • ¼ teaspoon baking soda to help with slight rise
  • ¼ teaspoon salt enhances chocolate flavor
  • ½ cup dark cocoa powder preferably rich, unsweetened
  • 1 ¼ cups all-purpose flour sifted for smooth dough
  • Toppings & Ganache:
  • ¾ cup semi-sweet chocolate chips for creamy ganache
  • ¼ cup heavy cream full fat for smooth ganache
  • Rainbow chip sprinkles for colorful decoration

Equipment

  • 1 Large mixing bowl For combining all ingredients.
  • 1 Electric mixer For creaming butter and sugars smoothly.
  • 1 set Measuring Cups and Spoons For accurate ingredient measurements.
  • 1 Cookie scoop (¼ cup) For portioning cookie dough evenly.
  • 1 Baking sheet For baking cookies in the oven.
  • 1 Parchment paper Prevents sticking and promotes even baking.
  • 1 Medium heat-safe bowl To melt chocolate for the ganache.
  • 1 Microwave or stovetop For heating cream for ganache.
  • 1 Fork or whisk For stirring and smoothing ganache.
  • 1 Refrigerator To chill cookies and set ganache.

Method
 

  1. Preheat your oven to 350°F (175°C).
  2. In a large mixing bowl, beat the softened butter, light brown sugar, and granulated sugar on medium-high speed until the mixture is light and fluffy, about 2 minutes.
  3. Add the egg, vanilla extract, and light corn syrup, mixing on low speed until fully incorporated. Scrape down the sides as needed.
  4. Sprinkle in the baking soda and salt, then mix briefly for 5–10 seconds until blended.
  5. Fold in the cocoa powder and flour, mixing on medium until the dough is uniform.
  6. Scoop ¼ cup portions of dough, roll into balls, and gently flatten each to a ½-inch thick disc.
  7. Arrange on a parchment-lined baking sheet and bake for 11–12 minutes. Allow centers to remain slightly soft.
  8. Let the cookies cool completely on a wire rack before adding the ganache.
  9. For the ganache, heat the heavy cream in a microwave-safe bowl until just bubbling, then pour over the chocolate chips in a separate bowl. Let sit for 3 minutes, then stir until smooth and creamy.
  10. Spoon 1 tablespoon of ganache onto each cooled cookie and sprinkle with rainbow chips.
  11. Refrigerate the cookies for 30–60 minutes to allow ganache to set. Serve chilled for optimal fudgy texture.

Nutrition

Serving: 1gCalories: 410kcalCarbohydrates: 51gProtein: 5gFat: 22gSaturated Fat: 13gPolyunsaturated Fat: 1gMonounsaturated Fat: 6gTrans Fat: 0.5gCholesterol: 63mgSodium: 130mgPotassium: 237mgFiber: 4gSugar: 30gVitamin A: 506IUVitamin C: 0.04mgCalcium: 44mgIron: 3mg

Notes

These cookies are perfect for sharing or gifting. The dense, fudgy centers pair beautifully with the sweet rainbow topping, creating a nostalgic and joyful treat every time.

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