Cut fillets into serving size portions; place in well-greased baking pan. Sprinkle fillets with 1 teaspoon salt and pepper. In skillet, fry bacon until lightly browned. Add mushrooms, onion and celery; cook and stir until tender. Stir in cooked rice, 2 tablespoons parsley and 1/4 teaspoon salt. Spoon a heaping 1/2 cup of rice mixture on top of each fillet. Drizzle melted margarine over rice. Bake, covered, in a preheated 350 degree oven until fish flakes easily when tested with fork (about 20 minutes).

To Serve: With long pancake turner, transfer to dinner plates. Spoon a dollop of Mushroom-Walnut Sauce over rice. Sprinkle with 3 tablespoons parsley. Pass remaining sauce.

In saucepan, saute 1 tablespoon minced shallot and 1 cup sliced mushrooms in 3 tablespoons butter. Blend in 3 tablespoons flour, 1/2 teaspoon salt, 1/2 teaspoon dry mustard and 1/4 teaspoon dried thyme. Gradually stir in 2 cups half and half. Cook over medium heat, stirring constantly, until mixture comes to a boil; boil and stir 1 minute. Stir in 1/4 cup chopped toasted walnuts.