Peanut Butter Swirl Bars
["1/2 c. peanut butter", "1/3 c. soft margarine", "3/4 c. firm brown sugar", "3/4 c. white sugar", "2 eggs", "2 tsp. vanilla", "1 c. flour", "1 tsp. baking powder", "1/4 tsp. salt"]
["Preheat oven to 350\u00b0.", "In large bowl, combine peanut butter, margarine, brown sugar and white sugar.", "Beat until creamy.", "Add 2 eggs and vanilla.", "Mix well.", "Then add flour, baking powder and salt."]
["peanut butter", "margarine", "brown sugar", "white sugar", "eggs", "vanilla", "flour", "baking powder", "salt"]