Preheat oven to 350°F.
Melt butter in 9×13-inch baking pan in the preheating oven.
Remove pan from the oven and sprinkle or pour the remaining 5 ingredients into the pan in even layers: first graham cracker crumbs, followed by chocolate chips, coconut, sweetened condensed milk and finally the chopped nuts.
Bake 20-25 minutes or until the top is browned. Cool before cutting into bars.
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