1 box devil's food cake mix (not pudding mix)
1 stick butter
3/4 c. creamy peanut butter
1 (7 or 7 1/2 oz.) jar marshmallow creme

Preheat oven to 350 degrees. Melt butter. Mix butter and cake mix in a large bowl. Take out 1 1/2 cups of mixture. Spread rest in ungreased 9 x 13 inch pan.

Mix peanut butter and marshmallow creme together and melt a little in a pot. Pour this on top of the spread cake mix. Sprinkle the reserved cake mix on top (lumpy and crumbly). Bake 20 minutes. Cool and cut into bars.