Preheat oven to 350 degrees F (180 degrees C).

Place butter in 13 x 9 inch pan and melt in oven. Swirl to coat bottom and sides with butter.

Spread crumbs evenly over bottom of pan. Press crumbs to lightly pack. Layer chocolate chips, butterscotch chips, coconut and nuts over crumbs. Last layere is the potatoe chips. Pour condensed milk over all layers.

Bake until edges are golden brown, about 25 minutes. Let cool.

Tip: I found letting the cookies sit before baking allowed the sweetened condensed milk to soak down into the other iingrediants which acts as a binder!!