Preheat oven to 325 degrees. In a large bowl, cream powdered sugar, vanilla, instant pudding and butter. Lightly spoon flour into measuring cup, level off. Stir flour, milk, vanilla and crushed candy bars into creamed mixture; mix well. Shape dough into 1-inch balls. Place on ungreased cookie sheets and bake in 325 degrees oven for 13-18 minutes or until edges are light golden brown. Cool. Dip top of cookie in powdered sugar, Makes 6 dozen.