Preheat the oven to 350°F and spray an 8x8-inch pan with non-stick spray.
Sift (or whisk) together granulated sugar, cocoa powder, flour, salt, and baking powder in a large bowl.
Melt butter and set aside to cool.
In a medium bowl, beat two eggs and vanilla extract with a hand-held mixer.
Add the egg mixture and melted butter to the dry ingredients. Stir until just incorporated.
Pour batter into the prepared pan and bake for 20-22 minutes.
