Peanut Butter Picnic Cake
["2 1/4 c. flour, plain", "2 c. packed brown sugar", "1 c. peanut butter", "1/2 c. butter or margarine, softened", "1 tsp. baking powder", "1/2 tsp. baking soda", "1 c. milk", "1 tsp. vanilla", "3 eggs", "6 oz. semi-sweet chocolate chips"]
["Grease bottom of a 9-inch x 13-inch baking pan.", "Set aside. Preheat oven to 350\u00b0.", "In large mixing bowl, combine flour, brown sugar, peanut butter, and butter.", "Beat until crumbly.", "Reserve one cup.", "Add baking powder, baking soda, milk, vanilla, and eggs. Blend until smooth.", "Pour batter into pan.", "Sprinkle reserved crumbs on top.", "Sprinkle chocolate chips over crumbs.", "Bake 35 to 40 minutes, or until a toothpick inserted in center comes out clean.", "Let stand in pan until cool.", "Cut into squares"]
["flour", "brown sugar", "peanut butter", "butter", "baking powder", "baking soda", "milk", "vanilla", "eggs", "semi-sweet chocolate chips"]