Cocoa brownies

Preheat the oven to 300 degrees F. Butter and flour an 8-inch square pan. In a mixer fitted with a whisk attachment, beat the eggs at medium speed until fluffy and light yellow. Add both sugars and blend. Add remaining ingredients, and mix to combine. Pour the batter into the pan and bake for 45 minutes. Check for doneness with the tried-and-true toothpick method: a toothpick inserted into the center of the pan should come out clean. When it's done, remove to a rack to cool. Resist the temptation to cut into it until it's mostly cool.