Preheat oven to 350°F. Line a 9x9-inch baking pan with a parchment sling. Spray with nonstick spray and set aside.
Add the butter and chocolate chips to a large microwave-safe bowl and microwave at 50% power in 30-second increments until melted. Stir and set aside to cool.
10 tablespoons unsalted butter, ½ cup semisweet chocolate chips
Whisk in the brown sugar, sugar, and eggs by hand until combined.
¾ cup brown sugar, ½ cup granulated sugar, 2 large eggs
Add the vanilla extract and whisk again.
1 teaspoon pure vanilla extract
With a wooden spoon or spatula, stir in the flour, cocoa powder, and salt.
¾ cup all-purpose flour, ¼ cup Hershey’s Special Dark Cocoa Powder, ¼ teaspoon kosher salt
Spread the batter out in your prepared pan and bake for 20-25 minutes, until the top is set and a toothpick inserted into the center comes out with a few moist crumbs.
Transfer the pan to a wire rack to cool for 30 minutes. Cover and place in the fridge to cool for 1-2 hours until no longer warm to the touch.
Once the brownies are cool, make the ganache. Add the chocolate chips to a medium bowl. Heat the cream in a small saucepan until it is steaming and starting to bubble around the edges of the pan. Pour the cream over the chocolate and let sit for 1-2 minutes. Whisk until smooth.
1½ cups semisweet chocolate chips, ½ cup heavy cream
Spread the ganache over the brownies. Top with sprinkles and transfer back to the fridge to chill until the ganache is set, about 45 minutes. Slice and serve.
¼ cup rainbow candy-coated chocolate chips