Mix powdered sugar and powdered milk thoroughly. Add peanut butter and softened butter. Stir in Rice Krispies. With a little powdered sugar on your hands form the rice krispies into walnut size balls. Place on a cookie sheet and freeze. In a double boiler melt chocolate. Insert a wooden skewer into the peanut butter krispies and dip in the chocolate until fully coated. Dip in bowls full of sprinkles, nuts or coconut. Place them on wax paper to dry. Or when the chocolate has dried you can melt the white chocolate and drizzle it over the top of the cookies. You can also use a squeeze bottle to decorate the cookies with the melted white chocolate. (You can buy squeeze bottles in the wedding section of most local stores) Also enjoy eating these treats frozen.