Add the fish fillets and cook 2- 3 minuts each side( cooking time depends on the thickness of the fillets). Transfer to a warmed plate and cover with foil to keep warm.
Reduce heat to medium low. Add the butter and chopped macadamias. Cook, stirring, for about a minute- until the butter and nuts are light golden brown. Watch carefully as you dont want the butter to burn.
Remove from the heat. Season with salt and pepper. Stir in the parsley.
Serve the fish and spoon over the macadamin and butter sauce. Serve with lemon wedges.