Preheat oven to 375°F

Beat butter, peanut butter and sugars until creamy. Beat in eggs. In separate bowl, sift flour, baking powder and salt. Stir into batter until well blended. Refrigerate 1 hour. Rill dough into 1 in balls and place on baking sheets. Flatten each ball with fork, making criss-cross pattern.

Bake 10 minutes or until cookies begin to brown. Do not overbake.