Alternatives and Variations

Champagne is not necessary for this sauce, but be careful to select a fairly austere white wine with relatively high acidity (such as Coteaux Champenois, Muscadet, Chablis, or Sancerre). If the ham used in the mirepoix is too salty, soak the slices in cold water for 30 minutes. The flavor of the sauce can be made more assertive by sweating the ham and mirepoix in ½ ounce (15 grams) butter until they lightly caramelize, before moistening with the wine.

Much of the character of this sauce comes from the mushroom cooking liquid or mushroom essence, so avoid trying to alter it by finishing the sauce with strongly flavored ingredients. The sauce is enhanced by wild mushrooms. A slice or two of dried cèpes (porcini) or a few reconstituted dried morels will work wonders. Wild or cultivated mushrooms, whole, chopped, or cut into julienne, make an attractive garniture for the finished sauce.