Basic Chocolate Cake with Chocolate Frosting

Heat oven to 350 °F (175°C). Grease and flour two 9-inch round baking pans or one 13 x 9 x 2-inch baking pan. For Cake: In a medium bowl, mix together flour, cocoa, baking soda, salt and baking powder; set aside. In a large bowl, combine butter, sugar, eggs and vanilla in large bowl and beat on high speed of mixer 3 minutes. Alternatively add flour mixture with water to butter mixture, beating until well blended. Pour batter into prepared pan(s). Bake 30 to 35 minutes or until wooden pick inserted in center comes out clean. Cool 10 minutes; remove from pans to wire racks. Cool completely. For Chocolate Frosting: Beat butter in medium bowl. Add powdered sugar and cocoa alternately with milk, beating to spreading consistency (additional milk may be needed, 1 teaspoon at a time until desired consistency). Frost cooled cake.