Bechamel with Mushroom Essence

Put a quarter of a pound of butter into a saucepan, add to it two ounces of onions cut in three-sixteenth inch squares, a quarter of a pound of lean veal cut in three-eighth inch squares, two ounces of carrots cut in one-quarter inch squares and two ounces of unsmoked ham cut in one-quarter inch squares, also a bunch of parsley garnished with two bay leaves and as much thyme, and let these fry on a moderate fire; drain off the butter, and add four quarts of veloute (No. 415), seasoning with salt, pepper and grated nutmeg, then cook the whole for one hour, afterward straining it through a tammy, and reduce it with one quart of essence of mushrooms (No. 392). Strain it again through the tammy and just when ready to use, incorporate into it half a pound of fine, fresh butter.