Scald, beard, and drain two dozen oysters, and put their liquor in a stewpan with a glassful of French white wine, some mushroom juice, and half a pint of white sauce of any kind; stir this over the fire to reduce by boiling for a quarter of an hour, then add three yolks and half a gill of cream, a little anchovy, a pinch of sugar, and the juice of half a lemon; stir again over the fire to set the leason, and strain the sauce into a small stewpan containing the oysters, and a like number of button mushrooms.
This sauce is intended specially for what is termed Matelotte Normande; but it is also well adapted for many other kinds of dressed fish.