THOUGH this dish should be served in scallop shells, ramekins make good substitutes. To fill four shells:




4 quarts mussels
DUCHESSE POTATOES
3 tablespoons butter, in all
21/2 tablespoons flour
11/4 cups broth from the mussels
1/2 clove of garlic
2 teaspoons minced parsley
2 egg yolks
Grated Swiss cheese

FOLLOW the directions for cooking and shelling mussels. Meanwhile, boil and mash the potatoes for the POTATOES DUCHESSE. When the mussels are done, strain the broth and let it test for a while away from the fire. Measure out the amount of broth specified for the sauce, and reduce it slightly over moderate heat.

Make a very light roux: Melt two thirds of the butter in a heavy saucepan, stir the flour into it, and cook over low heat, stirring constantly, until the mixture colors lightly. Set it aside to cool.

In another saucepan, cook the garlic in the remaining butter but do not let it brown. Add the reduced mussel broth and simmer together for a few moments. Meanwhile, finish the potatoes and put the purée in a pastry bag with a fluted tip.

Remove the garlic from the simmering broth, and stir the broth into the butter-flour roux. Stir over moderate heat until the sauce is well blended, then add the mussels and parsley. Simmer all together for 5 minutes. Then mix in the egg yolks, one at a time, stirring vigorously, and remove the pan immediately from the fire.