Cut into dice three ounces of the lean of a well-flavoured ham, and put them with half a small carrot, four cloves, a blade of mace, two or three very small sprigs of lemon thyme and of parsley, and rather more than an ounce of butter, into a stewpan; just simmer them from three-quarters of an hour to a whole hour, then stir in a teaspoonful of flour; continue the slow stewing for about five minutes, and pour in by degrees a pint of good boiling veal gravy, and let the sauce again simmer softly for nearly an hour. Strain it off, heat it in a clean saucepan, and when it boils, stir in a wineglassful and a half of good sherry or Madeira, two tablespoonsful of lemon-juice, some cayenne, a little salt if needed, and a small tablespoonful of flour very smoothly mixed with two ounces of butter. Give the whole a boil after the thickening is added, pour a portion of the sunce over the fish (it is served principally with salmon and trout), and send the remainder very hot to table in a tureen.
Obs.—a teaspoonful or more of essence of anchovies is usually added to the sauce, though it is scarcely required.