Prepare the Crust: Preheat your oven to 350°F (175°C). In a medium-sized mixing bowl, blend the graham cracker crumbs with the melted butter. Mix thoroughly until all the crumbs are well coated and evenly moist.

Form the Base: Press the graham cracker mixture firmly into the bottom of a 9x13-inch baking pan, creating an even crust layer.

Layer Ingredients: Drizzle the sweetened condensed milk evenly over the graham cracker crust. Add the rum (or rum extract) by sprinkling it over the condensed milk layer.

Add Coconut and White Chocolate: Evenly sprinkle the sweetened flaked coconut over the condensed milk layer, followed by the white chocolate chips.

Top with Pineapple and Nuts: Distribute the chopped dried pineapple and macadamia nuts over the chocolate and coconut layers.

Bake: Place the pan in the preheated oven and bake for 25-30 minutes, or until the edges are golden brown and the coconut is lightly toasted.

Cool and Cut: Remove the pan from the oven and allow the bars to cool completely before slicing into squares.