Cream together butter and peanut butter in large bowl with electric mixer. Gradually add confectioners sugar, using more or less to make an easily shaped dough. Shape into eggs and place on cookie sheet lined with foil or waxed paper. Candy will be slightly sticky. Refrigerate to firm. Melt chocolate and dip each egg with a fork. Remove from chocolate by sliding off fork with a toothpick onto lined cookie sheet. Refrigerate until chocolate sets.