Cream together margarine, peanut butter and sugars. Add eggs and beat for 3 minutes.
In a separate bowl mix flour, baking powder, baking soda and salt. Add to wet ingredients and mix just until combined.
Roll into small balls and place on baking sheet. Press down with a fork to make a hashtag design on top of the cookie. Bake at 375℉ for 8 - 10 minutes.