1/2 c butter
1/2 c creamy peanut butter
1/2 c packed brown sugar
1/2 c granulated sugar
1 egg
1 tsp vanilla
1 1/2 c all purpose flour
1/2 tsp baking powder
1/2 tsp baking soda
1/4 tsp salt
1 c chocolate chips

Mix butter and peanut butter, beat until light and fluffy.  Add egg and vanilla.  Mix, then add:  flour, soda, baking powder, and salt.
Shape 1/4 c dough into ball.  Place balls on greased cookie sheet about 5″ apart.  Flatten with glass dipped in sugar.
Bake 13-15 minutes at 350 or until firm.  Cool before eating.