Preheat oven to 350°F. Line a 9x13 pan with parchment or foil and grease lightly.
In a medium bowl, combine melted butter and graham cracker crumbs. Press evenly into the bottom of the pan.
Sprinkle evenly with coconut, nuts, chocolate chips and white chocolate chips, and drizzle with sweetened condensed milk.
Bake for 23-25 minutes until light golden brown (not too dark at the edges). Let cool completely before slicing.
