Preheat your oven to 350°F (175°C). Prepare an 8x8 inch baking pan by greasing it or lining it with parchment paper for easy removal.

In a medium bowl, melt the butter and let it cool slightly. Whisk in the granulated sugar and brown sugar until the mixture is smooth and well combined.

Add the cocoa powder, salt, and vanilla extract to the butter and sugar mixture, stirring well until everything is incorporated.

Next, whisk in the eggs one at a time until fully mixed.

Gently fold in the all-purpose flour and cornstarch, being careful not to overmix. The batter should be thick and glossy as you pour it into the prepared pan.

Bake in the preheated oven for 20-25 minutes. You’ll know they’re done when a toothpick inserted into the center comes out with a few moist crumbs attached.

While the brownies are baking, prepare the ganache by heating the heavy cream in a saucepan over medium heat until it simmers.

Remove it from the heat and add the chopped semisweet chocolate, stirring until the mixture is smooth and glossy.

Once the brownies have finished baking, pour the chocolate ganache over the top, spreading it evenly.

Sprinkle the rainbow candy-coated chocolate chips on top for a colorful finish.

Allow the brownies to cool to room temperature. For the best texture, refrigerate them for about 1 hour until the ganache is fully set.