Jelly Bean Mallow Bars 1 (18.25 ounce) box yellow cake mix 1/2 cup butter or margarine, melted 1 egg 3 cups miniature marshmallows 1 cup miniature jelly beans 1/2 cup cocktail peanuts, chopped Mix cake mix, butter and egg until well blended. Press onto bottom of greased 13 x 9-inch baking pan. Bake at 375 degrees F for 16 to 18 minutes or until light golden brown. DO NOT OVER-BAKE. Immediately sprinkle marshmallows, jelly beans and peanuts evenly over cake layer. Bake an additional 4 to 6 minutes or until marshmallows begin to melt. Cool completely in pan on wire rack. Cut into bars; store in airtight container.