Preheat the oven to 350 degrees. Spread the coconut out on a baking sheet and toast, stirring every 5-6 minutes until just barely golden. Remove from the oven and set aside.

Meanwhile, spray a 9 inch square baking pan with cooking spray then top with a sheet of parchment paper. Leave the parchment long enough to drape over the edges and act like a sling for lifting the bars out after baking. Spray the parchment with cooking spray.

Mix together the graham cracker crumbs and butter. Spread the mixture on the bottom of the baking pan, pressing it down with your fingers. Drizzle the condensed milk evenly over the top. Do not use a spatula to spread it, as this can mess up the crust.

In order, sprinkle the chocolate chips, caramel chips, coconut and cashews over the sweetened condensed milk. Press the layers into the milk gently with your palm so they stick. Bake for 25-30 minutes or until set. Cool completely (I'm serious on this one, you actually have to cool these completely or they're a gooey mess). Use the sling to lift the bars from the pan. Sprinkle with sea salt if desired. Cut into small-ish pieces (I usually get 16 bars out of this), and serve. Bars can be kept covered at room temperature or stored in the fridge. They'll last several days if you can keep yourself from eating them all!