• Preheat the oven to 350 degrees.
• Line a square 8x8 or 9x9 baking pan with parchment or foil and then spray it with non-stick spray. Set aside.
• Combine the melted cocoa powder, granulated sugar, melted butter, and brown sugar in a medium bowl. The mixture will be thick.
• Add in the eggs, egg yolk, corn syrup, and vanilla. Mix until thoroughly combined.
• Mix in the flour, cornstarch, and salt. Stir just until combined. The batter will be thick - that’s what you want.
• Transfer the batter to the prepared pan and spread it to the edges in an even layer.
• Bake for 25-30 minutes or until the center is set.
• Allow to cool before decorating.

Frosting

• Combine the chocolate chips and heavy whipping cream in a microwavable bowl. Heat for one minute.
• Remove from the microwave and stir until all the chips have melted and the ganache is smooth. Only if needed, heat for an additional 15-30 seconds or until all the chips have melted. Do not overheat.
• Pour the ganache frosting over the cooled brownies and spread it to the edges.
• Decorate with a light layer of sprinkles, rainbow morsels, or extra chocolate chips.
• Allow the brownies to cool in the fridge for about 2 hours or at room temp for about 4 hours before serving.