Preheat the oven to 350 degrees F (180 degrees C) or 325 degrees F if using a glass dish (160 degrees C).
Melt the Unsalted Butter (1/2 cup) in the microwave or on the stove top. Finely chop the Walnut (1 cup) preferably in a mini food processor.
Place the melted butter in a 9×13 pan (preferably glass, but aluminum works as well) and spread it out so that it evenly coats the bottom.
Sprinkle the Graham Cracker Crumbs (1 1/2 cup) on to the melted butter so that it is completely covered. Make sure you distribute the crumbs evenly. Once covered, pat the crumbs down a bit to make sure they stick together well.
Pour the Sweetened Condensed Milk (14 ounce) over top the graham cracker crumbs, again make sure you distribute evenly. Going slow here is important so that you get a nice, even coating.
Sprinkle the chopped walnuts evenly over the sweetened condensed milk.
Next, sprinkle on the Sweetened Coconut Flakes (1 1/3 cup) evenly over the top of the walnuts.
Lastly, sprinkle on the Semi-Sweet Chocolate Chips (1 cup). Press down gently across the top to bind all the ingredients together.
Bake in the preheated oven for 25-30 minutes. The edges should just be starting to brown.
Allow to cool completely (leaving it overnight is best) before cutting. Cut into 1.5 x 2 inch rectangles to get about 36 bars. One row of bars will be a little bigger, but you can really cut them to whatever size you like.
These can be stored in an air tight container at room temperature. They last for at least 1-2 weeks.