S'More Cookie Bars
["1/2 c. (1 stick) butter or margarine, softened", "3/4 c. sugar", "1 egg", "1 tsp. vanilla", "1 1/3 c. all-purpose flour", "3/4 c. graham cracker crumbs", "1 tsp. baking powder", "1/4 tsp. salt", "4 (1.55 oz.) Hershey milk chocolate bars", "1 c. marshmallow cream"]
["Preheat oven to 350\u00b0.", "Grease 8-inch square baking pan.", "In large mixer bowl, beat butter and sugar until light and fluffy. Add egg and vanilla; beat well.", "Stir together the flour, graham cracker crumbs, baking powder and salt; add to butter mixture, beating until blended."]
["butter", "sugar", "egg", "vanilla", "flour", "graham cracker crumbs", "baking powder", "salt", "milk chocolate", "marshmallow cream"]