1/2 cup peanut butter
1/3 cup butter or margarine
1 cup sugar
1/4 cup packed brown sugar
2 eggs
1 cup flour
1 teaspoon baking powder
1/4 teaspoon salt
1 package (6 oz.) chocolate chips
1/2 teaspoon vanilla extract

Beat first two ingredients until blended. Gradually add sugars and beat until fluffy. Add eggs, one at a time, beating well after each. Add dry ingredients and mix well. Stir in chocolate chips and vanilla and spread in buttered 9 inch square pan. Bake in moderate oven (350) for 30-35 minutes. Cool in pan on rack then cut into 2-1/4 inch squares. Makes 15 chewy brownies.