Blend the macadamia nuts and breadcrumbs together until it is coarsely ground mixture. Dip the fillets into the blend; make sure each side is coated evenly.
Panfry the shallots until they are translucent. Slowly add the chicken stock then the papaya, pineapple (optional) and mango. Add sugar, salt and pepper to taste. The sauce will thicken, which will take about 20 minutes.
In another pan, place the butter in a pan or skillet and let it sit over medium heat. Once the butter has melted, pan fry the fish front and back until the fish is cooked and the nuts are a rich golden brown color.
. Drizzle the sauce over the fillets. Generously add the fruit from the sauce and shredded coconut to the top of the mahi-mahi.