You’ll Need:Nonstick cooking spray 1 1/2 cups butter, softened 1 1/2 cups plus 2 tablespoons granulated sugar Grated zest of 2 large lemons (reserve the juice for the lemon syrup) 5 eggs, divided (5 yolks and 5 whites) 1 1/2 cups sour cream or plain yogurt 1 tablespoon vanilla extract