Ingredients: Chablis, mushrooms, leeks, a bunch of herbs, peppercorns, Espagnole sauce, game gravy or stock, lemon.
Put into a stewpan two glasses of Chablis, two tablespoonsful of mushroom trimmings, a leek cut up, a bunch of herbs, five peppercorns, and boil till it is reduced to half. In another stewpan mix two glasses of Espagnole sauce (No. 1) or Velute sauce (No 2) and half a glass of game gravy, boil for a few minutes then blend the contents of the two stewpans, pass through a sieve, and add the juice of a lemon.
See also: Wikipedia Cookbook.
Source: ''The Cook's Decameron: A Study In Taste, Containing Over Two Hundred Recipes For Italian Dishes'' from a project that puts out-of-copyright texts into the public domain. This is from a *very* old source, and reflects the cooking at the turn of the last century. Update as necessary.