Peanut Butter Cookie Bars Recipe

Preparation: Preheat oven to 350 F. Line a 9 x 13-inch pan with non-stick foil. In a large bowl, cream butter, shortening, peanut butter , egg, and vanilla . Beat in brown sugar. Add flour and salt , beating until combined. By hand, stir in two-thirds of the 1/3 cup chopped peanuts, reserving the remainder for the topping. Batter will be thick. Press peanut butter cookie dough into an even layer in the prepared pan. Bake 15 to 20 minutes, until lightly browned. Do not overcook. Let cool to room temperature, then prepare the topping. For the topping, heat the peanut butter in the top of a double-boiler until warm. Add the chocolate chips, stirring until melted, then stir in the remaining chopped peanuts. (Alternatively, the chocolate and peanut butter may be melted slowly in the microwave, checking and stirring every 30 seconds, but take care not to scorch the chocolate or it will seize up and get hard.) Remove from heat and let cool slightly, then spread on top of cookie layer. Sprinkle with marshmallows , pressing them gently into the chocolate so they stick. Refrigerate about 20 minutes to set chocolate. Cut and serve peanut butter cookie bars at room temperature. Yield: 36 to 48 servings, depending on cut size Note: If you don't want to buy a full can of peanuts just for this recipe, pick up a single serving snack package of peanuts, usually sold near the check-out counters of grocery stores and convenience stores. Peanut Butter Cookie Bars Recipe Photo © 2010 Peggy Trowbridge Filippone, licensed to About.com, Inc.