Preheat oven to 350 degrees. Grease a 9 x 13 baking pan with cooking spray or butter.
Crush graham crackers in a food processor or a ziplock bag into fine crumbs with no large pieces.
Pour graham cracker crumbs into the baking pan. Pour melted butter right on top of the crumbs. Mix until crumbs are coated with butter.
Spread graham cracker crumb mixture along the bottom of the baking pan until it is covered completely. Use a spatula or the bottom of a flat measuring cup to press and flatten the crumb mixture lightly.
Spread the chocolate chips and the butterscotch chips on top of the graham cracker crust until evenly distributed.
Top it off with the chopped nuts to your desired amount.
Pour sweetened condensed milk evenly on top, so the entire pan is covered.
Spread shredded coconut evenly on top of sweetened condensed milk.
Bake for 25 - 30 mins until the condensed milk layer is mostly caramelized and browned.
Let it cool completely before cutting. Using a butter knife to scrape along the edges of the pan gently will help release the cookie bars from the pan.