Makes 6 dozen.

Preheat oven to 350°

In a small bowl, stir flour, baking powder, baking soda, and salt. In large bowl with mixer at medium speed, beat margarine and peanut butter until smooth. Beat in sugars until blended. Beat in eggs and vanilla. Add flour mixture and beat until well blended. If necessary, refrigerate dough.

Shape into 1-inch balls and place 2 inches apart on ungreased cookie sheets. Flatten with fork, dipping in sugar and making crisscross patterns.

Bake at 350° for 12 minutes or until lightly browned. Remove from cookie sheets and cool completely on wire racks. Store in tightly covered container.