Fish Supreme(Walleye, Lake Trout, Etc.) - cooking recipe

Ingredients

1 to 2 lb. fish (fillet)
1 small onion, chopped
1 to 2 Tbsp. butter
1/2 c. cream
1/2 c. sliced mushrooms
2 egg yolks
1 tsp. parsley
salt and pepper
garlic (optional)
1 c. water

Preparation

Place fish fillets in shallow baking dish with water, salt and pepper.
Cook until done but still firm.
There should still be liquid in the dish.
Saute the chopped onion and mushrooms in the butter for 5 minutes. Add liquid from the fish and cook 5 minutes, then thicken with the cream, yolk and parsley mixture.
Place fillets on serving dish and pour or spoon sauce over fish.