Oysters Au Gratin
Rinse the oysters. Carefully open them and remove the oyster meat and any liquid. Rinse the shells, pat dry and arrange on coarse salt on a plate.
Bring the fish stock to a boil with the oyster water (after passing it through a sieve). Blanch the oysters for 5 seconds. Keep them warm in the shells.
Heat the butter until foamy and stir in the flour. Add the Noilly Prat and wine. Simmer. Reduce the blanching liquid and add it to the wine sauce. Add the cream and season with salt, pepper and cayenne. Remove from heat.
Mix the egg yolk with 1 tablespoon of melted butter and stir into the sauce.
Coat the oysters with the sauce and bake until golden. Garnish with caviar and dill sprigs.