Lyonnese Sauce with Tarragon

Cut up eight ounces of onions into three-sixteenth inch squares; blanch, then drain and fry them in two gills of oil or else six ounces of butter; when nearly done, put them into a saucepan with one pint of veal blond (No. 423), one pint of espagnole (No. 414) or veloute sauce (No. 415), and one tablespoonful of meat glaze (No. 401); reduce it, then add the juice of a lemon, some nutmeg, and mignonette. Strain the sauce through a tammy (No. 159), then incorporate into it four ounces of butter and a teaspoonful of tarragon leaves finely shredded and blanched.