Preheat oven to 350º. Line an 8 x 8-inch baking pan with non-stick foil.

In a large, microwave-safe bowl, melt the butter using 30-second increments

Add the sugars and mix to combine. Then add the eggs, vanilla, and stir till well mixed.

Add the cocoa powder and whisk until smooth.

Add the flour, cornstarch, and baking powder and stir until it's blended,

Pour batter into prepared pan, smoothing the top lightly with an offset spatula.

Bake for 28-32 minutes until the top looks set and a toothpick inserted into the center comes out clean or with just a few crumbs. Cool on a wire rack.

While brownies have cooled for at least a half-hour, make the ganache.

Add chocolate chips and cream to a medium, microwave-safe bowl, and microwave on high for one minute. Set aside.

Let stand a few minutes before whisking to combine. If there are any small lumps, you may microwave for 15 seconds and whisk until smooth. Repeat if needed.

Pour the ganache over the brownies and smooth with an offset spatula.

Sprinkle with sprinkles and chill for at least 2 hours before cutting.