Length-wise, roll one half into the macadamia nuts and the other half into the Wattleseed
Place the leg into a hot oven and cover with aluminum foil ensuring that the plasticized metal does not touch the food. Use a piece of baking paper, if necessary. Roast for 1 and a half hours at 200 degrees C and then remove the covering and roast until the nuts are just browned. Use a meat thermometer for accurate measurement of the doneness. Remove from the oven and allow to rest for 15 minutes before carving, remembering to remove the string.
Place the mango puree, Mintbush marinade, butter, salt and pepper into a saucepan. Warm for a few minutes on a medium heat.
Slice the lamb leg and fan on a plate over Lemon myrtle infused rice, Rainforest herb fettuccini or Alpine pepper polenta. Drizzle with the mango sauce and accompany with your favorite steamed greens or baked vegetables.