Preheat oven to 350°F. In large bowl cream butter, peanut butter, shortening and sugar until light and fluffy; beat in egg and vanilla. In medium bowl combine flour, baking soda and baking powder; blend into creamed mixture. Stir in "M&M's"® Milk Chocolate Mini Baking Bits and nuts. Drop by rounded teaspoonfuls onto ungreased cookie sheets. Bake 8 to 10 minutes or until light golden brown. Let cool 2 minutes on cookie sheets; remove to wire racks to cool completely. Just before serving, spread 1/2 teaspoon jam on bottom of one cookie; top with second cookie. Store in tightly covered container.