Copeland's of New Orleans the Guitreau

Source: Copeland's of New Orleans

4 ounces butter
4 ounces chopped onions
5 single mushrooms
1/2 teaspoon salt
3/4 teaspoon garlic powder
1/4 teaspoon white pepper
8 ounces fish fillet (red or black drum recommended)
4 ounces crawfish tails
4 ounces 90-100 size shrimp

Cook fish on grill approximately three minutes on each side. While fish is cooking, saut