DIRECTIONS
In a large mixing bowl, cream butter and sugar until light and fluffy. Beat in egg and vanilla. Combine the flour, cocoa, baking powder and salt; gradually add to creamed mixture until well blended. Stir in 1/2 cup M&M's and 1/4 cup walnuts.
Spread onto a greased 14-in. pizza pan to within 1/2 in. of edges. Sprinkle with remaining M&M's and walnuts. Top with marshmallows and coconut. Bake at 350° for 15-20 minutes or until a toothpick inserted near the center comes out clean. Cool on a wire rack. Cut into wedges. Yield: 10-12 servings.