Line 2 cookie sheets with waxed paper. Beat the peanut butter, margaine and vanilla together until smooth. Slowly beat in powdered sugar and flour until well blended. Roll rounded teaspoonsful of dough into balls and push up to make a point. Refrigerate until firm. Dip flat part of cookie into melted chocolate, halfway up. Roll in chopped nuts. Place on cookie sheets and put in refrigerate until chocolate is set. Makes about 60 cookies. ----