Preheat the oven to 350°F Now if you want to only have one dish to wash then put your 9"x13" pan in the oven with your butter and once the butter has melted take the pan out and add your crumbs. Press the crumbs in to make an even packed layer. You can also just melt the butter in the microwave.
Sprinkle all of the ingredients on one at a time.Chocolate ChipsButterscotch ChipsCoconutwalnutsSweetened condensed Milk
Bake for 25-30 mins. Let chill in the pan before removing and slicing.