Remember your favorite pre-made brownies? You know the ones, with the little curly-haired girl in a hat on the box. The brownies that were perfect when thrown into a lunchbox, savored on the bus ride home or enjoyed after school with a tall glass of cold milk in front of the TV.

Well, we upgraded those fan-favorite brownies by making them from scratch and adding our Wilton Rainbow Chip Crunch Sprinkles on top for a sweet crunch! The super moist brownie and sweet chocolatey ganache pair well with the crunch of the sprinkles for a little taste of nostalgia to bring you back to simpler times. 

Rainbow chip brownies on parchment paper with Wilton Rainbow Chips

Rainbow Chip Brownies

Serve up nostalgia in brownie form by whipping up a batch of these cosmic brownies topped with playful rainbow chips. Super moist and chocolatey with a slight crunch from the Wilton Rainbow Chip Crunch Sprinkles, these easy but impressive brownies are sure to bring up fond back to school memories and make lunchtime fun!
4.80 from 5 votes
Prep Time 20 mins
Course Dessert
Servings 16 2”x 3” Brownies


  • 9 x 13" Metal Baking Pan
  • Large Bowl
  • Sifter
  • Medium Bowl
  • Medium Microwave-Safe Bowl



  • 1 cup All-purpose flour
  • ¾ cup Unsweetened cocoa powder
  • ½ tsp Salt
  • ½ cup + 2 tbsp Vegetable oil
  • 1 ½ cups Brown sugar
  • 2 Whole eggs + 2 Egg yolks
  • 2 tbsp Light corn syrup
  • 1 tbsp + 1 tsp Vanilla extract


  • 1 ⅓ cups Semi-sweet chocolate chips
  • 3 oz Heavy cream
  • 1 tbsp Vanilla extract
  • 2 tsp Corn syrup
  • 1 pinch Salt



  • Preheat oven to 350F and line a metal 9 x 13” baking pan with parchment. Lightly grease with cooking spray. 
  • Sift flour, cocoa powder, and salt into a large bowl and whisk to combine.  
    Whisk in cocoa powder mix
  • In a separate medium bowl, whisk together the oil, brown sugar, eggs and yolks, corn syrup, and vanilla extract until well combined. 
  • Pour wet ingredient mixture into the dry ingredients and stir until just combined and no dry ingredient streaks or clumps remain.  
    Whisking wet ingredients in glass bowl
  • Spread batter into the prepared pan in an even layer.  
    Spread batter evenly into parchment paper lined baking pan
  • Bake for 15-20 minutes, or until a toothpick inserted into the center comes out clean (just a crumb or two stuck to the toothpick is ok). Leave brownies in the pan and set aside until ready to top with ganache.  


  • Stir all ingredients together in a medium sized microwave-safe bowl.  
  • Microwave for 30 seconds, and stir.  
  • Microwave for an additional 15 seconds and stir again. Allow the residual heat to continue to melt the chocolate as much as possible. 
  • If there are still small solid pieces of chocolate remaining, microwave in several second bursts and then stir until ganache is smooth. 


  • While ganache is still warm (microwave for several seconds to warm back up if needed), spread in an even layer over the brownies. (Brownies can still be warm during this step)
    Spread ganache onto brownies in baking pan
  • Immediately sprinkle on Wilton Rainbow Chip Crunch Sprinkles. Enjoy! 
  • Optional but recommended: Allow brownies to chill in freezer for 1 hour, or the fridge for a few hours to fully set the ganache and firm up the brownies before cutting.  
    Side view of brownies topped with ganache and Rainbow Chip Crunch Sprinkles


Tip: For super clean cuts, clean your knife off in between each cut. Cut brownies into 16 2x 3pieces to replicate a similar size to the original cosmic brownie. Bonus step, drag a knife through the ganache in the middle of the brownie bars to create the indent line from the original look as well.
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