Preheat oven to 350 degrees F (175 degrees C).

Spray the bottom of a 9x13 inch pan with non-stick spray.

Combine coconut cookie crumbs, flaked coconut, and chopped macadamia nuts in the pan.

Drizzle with melted butter and stir to combine.

Press the mixture firmly onto the bottom of the pan to form the crust.

Bake for 15 minutes.

Cool the crust completely.

In a mixing bowl, combine cream cheese and sugar.

Mix until the mixture is fluffy and smooth.

Blend in sour cream until well combined.

Gently fold in Cool Whip.

Spread the cheesecake mixture evenly over the cooled crust.

Refrigerate to allow the cheesecake layer to set.

In a saucepan, combine coconut milk, sugar, and cornstarch (dissolved in 1/4 cup cold water).

Cook over medium heat, stirring constantly, until the mixture thickens to a custard-like consistency.

Remove from heat and continue stirring constantly while cooling to prevent skin formation.

Once the haupia is cool to the touch, spread it evenly over the cream cheese layer.

Sprinkle with chopped macadamia nuts or shredded coconut, or both, for garnish.

Refrigerate the cheesecake for at least 2 hours to set completely before serving.

Variation: For Pina-colada cheesecake, drain 1 large can of crushed pineapple and stir in 1/2 cup of sugar.

Spread the pineapple mixture onto the crust before adding the cheesecake layer.

Add 1 teaspoon of rum flavoring to the cheesecake layer.