Chocolate Brownies
["1/2 c. plus 3 Tbsp. reduced calorie margarine, softened", "1 1/3 c. sugar", "8 egg whites", "1/2 c. nonfat sour cream alternative", "1/3 c. evaporated skimmed milk", "2 tsp. vanilla extract", "1 1/3 c. all-purpose unbleached flour", "1 tsp. baking powder", "1/2 tsp. salt", "2/3 c. unsweetened cocoa", "vegetable cooking spray", "Creamy Chocolate Frosting (recipe to follow)"]
["Beat margarine at medium speed of electric mixer until fluffy. Gradually add sugar and beat well.", "Add egg whites, sour cream, milk and vanilla; beat well.", "Combine flour and next 3 ingredients; stir well.", "Pour into a 13 x 9 x 2-inch pan coated with cooking spray.", "Bake at 350\u00b0 for 25 minutes or until toothpick inserted in center comes out clean.", "Cool on a wire rack.", "Frost with Creamy Chocolate Frosting and cut into 24 squares."]
["margarine", "sugar", "egg whites", "nonfat sour cream alternative", "milk", "vanilla extract", "all-purpose unbleached flour", "baking powder", "salt", "unsweetened cocoa", "vegetable cooking spray", "Chocolate Frosting"]