Peanut Butter Bars
["1/2 c. peanut butter", "1/2 c. margarine", "1 1/2 c. sugar", "2 eggs", "1 1/2 tsp. baking powder", "1/2 tsp. salt", "1 tsp. vanilla", "1 c. plain flour"]
["Mix all ingredients well by hand.", "Bake in a 9 x 12-inch pan at 350\u00b0 for 25 to 30 minutes."]
["peanut butter", "margarine", "sugar", "eggs", "baking powder", "salt", "vanilla", "flour"]