Laguipierre Sauce

Pour into a saucepan a quarter of a bottleful of white wine or champagne, add to it two ounces of chopped mushrooms, one tablespoonful of chopped and blanched shallots, half a clove of garlic, one bay leaf, six grains of allspice, eighteen grains of pepper, and let all these simmer together with two gills of veal blond (No. 423) for fifteen minutes, then add one pint of veloute (No. 415), and one gill of reduced mushroom essence (No. 392); thicken the sauce with four egg-yolks and one gill of cream, strain the whole through a tammy (No. 159), and then beat into it two ounces of fresh butter and the juice of one lemon.