Prepare 2 ounces (50 grams) julienned mushrooms. Simmer the julienne for 5 minutes in 5 fluid ounces (150 milliliters) white wine. Strain the wine and save the mushroom julienne to add to the sauce at the end. Return the white wine to the saucepan and reduce it by half. Add 7 fluid ounces (200 milliliters) demi-glace, 1 cup (250 milliliters) tomato sauce, and ¼ cup (60 milliliters) white chicken or veal stock. Gently simmer and skim for 5 or 10 minutes, until it has a lightly syrupy consistency. Strain the sauce through a fine chinois, and finish it with the julienned mushrooms as well as 2 tablespoons (30 milliliters) unsmoked cured ham cut into fine julienne and 1 tablespoon (15 milliliters) black truffles, also cut into julienne.