From: The Thorough Good Cook

Sauces: 25. Geneva

Take a few mushrooms, onions, carrots sliced, parsley, a sprig of thyme, a bay-leaf, two ounces of ham, two cloves, a blade of mace, and peppercorns; pass the whole over the fire with a little butter. When it becomes clear, add a tablespoonful of flour, stir it well over the fire a few minutes, and add good consommé to bring it to the consistence of cream; with this put half a bottle of sherry or Madeira. Let the whole simmer until the roots are done; skim it well, and strain it over whatever fish you have occasion to dress. When the fish is done, take it carefully up with a slice, drain it, and put the sauce into a stew-pan; boil it, and skim off the fat. The moisture from the fish will thin your sauce; you will, therefore, reduce it by boiling. Add a little flour and butter kneaded; finish with a little anchovy butter, lemon juice, and cayenne, and mask the fish with it.