In a small bowl, whisk together the cornstarch and sugar and set aside.

 In another small bowl, add eggs and beat well with a fork.

 In a medium saucepan, add coconut milk and milk.  Cook over medium heat until warm and then add sugar/starch mixture.  Whisk vigorously until the sugar and starch are dissolved.  Remove the pan from the heat.

 Scoop out about 1 cup of the hot milk mixture.  Pour a couple tablespoons of the hot milk into the bowl with the eggs.  Whisk together.  Continue adding just a bit of the hot milk at a time, while mixing, until you have added enough that the eggs are warm, and you have added the full cup of hot milk.  Now, pour the warm egg/milk mixture into the pan of mil an whisk together well.

 Return the pan to the heat and continue cooking while slowly whisking almost constantly.  Bring mixture to a slow boil and boil (while whisking) about 1 minute. the mixture should now be thickened.

 Remove the pan from the heat and whisk in vanilla and coconut extract.

 Allow to cool a few minutes (string occasionally), then lay a piece of plastic wrap or parchment paper directly on the surface of the pudding to prevent a skin from forming.  Move to the fridge and chill at least 4 hours (and up to 3 days).

 Preheat oven to 375°F.

 Rough chop macadamia nuts (chop so they are not whole, but are still moderate sized chunks), and set aside.

In a large plastic ziplock bag, add vanilla wafers and crush with a rolling pin (or any object) until the cookies are crushed with various sized pieces (some crumbs, some larger pieces).

 In a large bowl, add crushed vanilla wafers, macadamia nuts and coconut.  Drizzle melted butter over mixture, then stir to evenly coat.

 Spread mixture onto a rimmed cookie sheet and bake about 10 minutes.  It's very important to check on the mixture, and stir every 2-3 minutes.  Remove from oven when the coconut is a nice golden brown.  Set aside to cool.

  If you also have the larger coconut slices to use as garnish, add those to their own baking sheet now and bake in the preheated oven for 2-3 minutes (watch closely so they do not burn).  Set aside to cool.

Chill the bowl and beater (whisk attachment) of your electric mixer by placing them in the freezer about 5 minutes.

When the bowl has chilled, pour cream into bowl and begin whipping on medium-high speed.

When the cream is beginning to thicken, slowly add the powdered sugar, while continuing to beat.

Add vanilla, while mixing.

The whipped cream is done when it has more than doubled in volume and, when you stop the mixer and lift up the whisk, the cream stays in place.  Do not over-mix or the cream will become too thick and will become clumpy.

To assemble, add a layer of crumble, then pudding, then whipped cream to your desired dish.  Repeat layers, and then garnish with a bit of crumble and some large pieces of toasted coconut (if desired).

Enjoy!