1/2 c. peanut butter, plain or crunchy
1/3 c. butter
1 c. granulated sugar
1/4 c. packed brown sugar
2 eggs
1 c. flour
1 tsp. baking powder
1/4 tsp. salt
1 (6 oz.) pkg. chocolate chips
1/2 tsp. vanilla

Beat first two ingredients until blended. Add sugars gradually. Add eggs, one at a time, blending after each. Add dry ingredients and blend. Stir in chocolate chips and vanilla. Pour in buttered 9-inch square pan; double recipe for 9x13 inch pan. Bake at 350 degrees for 30-35 minutes. Cool on cake rack.