In a medium bowl sift flour and baking powder and set aside.Cream together butter, peanut butter and sugar until fluffy. Beat egg into mixture and follow with the flour mixture. STIR. Make teaspoon balls and place 2" apart and flatten with a fork into a crisscross pattern. Bake for 18-22 min. Quickly transfer to a cooling rack as these are pretty delicate after they come out of the oven. Cool. Store in an air tight jar for up to a week....but I doubt they'll last that long!!! *** You can reduce the amount of sugar to 3/4 cup if you don't want them to be that sweet!