Cream Cheese Frosting
For brownies: In a small bowl, combine flour, baking soda, baking powder and salt.Advertisement
In a large mixing bowl, beat eggs with electric mixer on low speed until combined. Add sugar, oil and melted chocolate; beat until blended. With mixer on low speed, add flour mixture. Beat just until well combined. With a spoon, stir in zucchini and nuts. Turn batter into a greased and floured 15x10x1-inch baking pan. (For thicker brownies, use a 13x9x2-inch pan.)
Bake in a 350° oven for 30 to 35 minutes or until surface springs back when pressed lightly. (Bake for 25 to 30 minutes if using a 13x9x2-inch pan.) Cool in pan on wire rack.
Meanwhile, make Cream Cheese Frosting. In a large mixing bowl, beat cream cheese, butter and vanilla with an electric mixer on medium speed until light and fluffy. Gradually beat in powdered sugar to reach spreading consistency. Spread over cooled brownies in pan. Serve immediately or store, covered, in refrigerator.