1. Stir together flour, baking powder, salt and cocoa. Set aside.
2. In medium mixing bowl, beat together margarine and sugar until light and fluffy. Add egg and vanilla. Beat well. Add KELLOGG'S CORN FLAKES cereal and flour mixture; mixing until combined. Drop by tablespoons onto ungreased baking sheet.
3. Bake at 350° F about 12 minutes or until done. Cool.
4. When cookies are cool, combine frosting ingredients and stir until smooth. Fill icing bag with frosting and draw bat design on each cookie. Store in airtight container.
Yield: 3 1/2 dozen (42) cookies
Note Prepared frosting can be used in place of making frosting. Use candy sprinkles to add color to cookies.