PREHEAT oven to 325° F. Grease 9-inch-square baking pan.
BEAT flour, graham cracker crumbs, butter, granulated sugar and brown sugar in large mixer bowl until mixture resembles fine crumbs. Stir in 1/2 cup Buncha Crunch. Press into prepared baking pan.
BAKE for 15 minutes. Remove from oven. Dot with marshmallow creme. Let stand for about 5 minutes to soften; spread evenly over surface.
BAKE for an additional 10 minutes. Remove from oven. Sprinkle with remaining Buncha Crunch in a single layer. Press in gently with spatula. Cool completely in pan on wire rack.