2 doz. oysters on the half shell, drained
4 pans rock salt

BIENVILLE SAUCE:

1/2 c. (1 stick) salt butter
1 c. finely chopped shallots
1/4 c. finely minced parsley
1 1/2 tsp. finely minced garlic
1/2 c. flour
1/2 c. heavy cream
1 1/2 c. milk
4 lg. egg yolks, well beaten
1/4 c. dry sherry
1 tsp salt
1 tsp. freshly ground white pepper
1/2 tsp. cayenne
2/3 c. finely chopped mushrooms
1/2 lb. shrimp, boiled and diced fine

TOPPING (OPTIONAL) :

6 tbsp. freshly grated romano cheese
4 tbsp. dried bread crumbs
3/8 tsp. paprika
1/2 tsp. salt

To prepare the sauce, in a large heavy saucepan melt the butter over low heat. Add the shallots, parsley, and garlic and cook, stirring frequently, until quite soft, about 10 minutes. Gradually stir in the flour and mix with a wooden spoon until smooth, then add the milk, cream, egg yolks, sherry, salt, pepper and cayenne; blend thoroughly, then continue cooking over low heat until the mixture begins to thicken. Stir in the mushrooms and cook for 2 minutes, then add the shrimp and continue to cook over low heat for about 3 to 4 minutes, until the sauce is quite thick. Spoon the sauce into a large, shallow porcelain or glass dish, to a depth of 1 1/2 to 2 inches. Let cool for a few minutes at room temperature, then cover with plastic wrap and refrigerate for at least 1 1/2 hours.

Half an hour before you plan to bake the oysters, place the pans of rock salt in the oven preheated to 500 degrees.

To prepare the oysters for baking, wash the shells well and dry them. Put an oyster on each shell and set them 6 to a pan on the rock salt, spooning 1 heaping tablespoon of sauce evenly over each oyster. Prepare optional topping by spinning all ingredients in a blender or processor for a few seconds. Sprinkle 1 tsp. evenly over each sauced oyster. Bake for 15 to 18 minutes or until browned.