Shells St. Jacques Alla Breton

Preparation:

Preparation: Open the shells, using a small knife and detaching the shells; then extract the molluscs. Separate the nuts from the corals, removing the nerves and other adhesions. Put nuts and corals to purge in cold water; meanwhile carefully wash the shells that contained the molluscs. Melt half of the butter in a large, shallow saucepan and add the chopped onion. Add the well-drained walnuts and corals to the sautéed pan: let them flavor for a few moments, then pour over the white wine and let it evaporate slightly. Cover the molluscs with water, salt and pepper and cook for 10 minutes. Meanwhile, melt the remaining butter in another saucepan and dilute the flour, but do not let it brown too much. Extract the molluscs from their cooking bottom; filter the latter through a fine-mesh sieve and pour it over the butter and flour mixture, stirring constantly with a wooden spoon. Then add the cream and, without ceasing to stir, cook and thicken the sauce for a few minutes. Break the egg and put the yolk, together with a spoonful of water, in another saucepan over a very low heat: beat it with a small whisk until it becomes creamy; then add it to the sauce that you have removed from the heat. Season with salt and pepper, if necessary, and keep warm for a few minutes in a bain-marie. Cut walnuts and corals into slices and distribute them, alternating them, in the shells. Cover with the sauce. Now arrange the shells on a heat-resistant plate and brown them under the oven grill for a few minutes. Serve them very hot.