This section is from the book "The Epicurean", by Charles Ranhofer. Also available from Amazon: The Epicurean, a Complete Treatise of Analytical and Practical Studies on the Culinary Art.
This crustacean has the head and the corselet blended in one single piece, having attached five pairs of feet; the tail is more or less apparent. Crawfish are aquatic and turn red when cooked. Persons suffering from a weak stomach should avoid partaking of them, as they are very indigestible, but they are delicious for those who are able to indulge in them. They are useful for decorating cold dishes and entrees, and are used by themselves in the form of pyramids.
Procure three dozen live crawfish, wash them thoroughly, place them in a net, and plunge them for two minutes into plenty of boiling water in order to kill them, then remove and break off the small legs. Fry three very finely chopped shallots in butter with six ounces of minced mush-rooms, thyme and bay leaf, add the crawfish and moisten with white wine; let cook for ten minutes, suppress the thyme and bay leaf, season with salt and red pepper, and just when prepared to serve add half an ounce of fresh butter and some chopped parsley.
Choose live crawfish; set them inside a net, wash them well, and plunge them rapidly into boiling water, leaving them in only sufficiently long to kill, then drain and pick off the small legs. Fry a mirepoix of roots and minced onions in oil, moisten with white wine, season, and add aromatic herbs, a bunch of parsley and a few spoonfuls of brandy; let the whole boil for several minutes, then throw in the crawfish and cook them from ten to fourteen minutes according to their size, while tossing steadily. Take them off the fire, strain the broth through a sieve, leaving the crawfish in the saucepan. Cut in small three-sixteenth of an inch squares or in Julienne, some red part of carrots, and tender celery roots, parboil both in salted water, and then drain, fry without coloring in some butter, onions, cut in three-sixteenths of an inch squares, add to it the roots, and fry together for a few minutes, then moisten with two or three spoonfuls of broth and the crawfish stock; let the liquid fall twice to a glaze so that the vegetables are well cooked, and moisten again with the stock of the crawfish reduced to a half-glaze. Cook together for five or six minutes, then thicken with small pieces of butter kneaded with flour, adding also two or three spoonfuls of Madeira wine and a dash of cayenne pepper; remove the sauce to the side of the fire in order to add butter to it.
Dress the crawfish on a deep dish with a little of their own broth, and serve the sauce in a separate sauce-boat.
To prepare the court bouillon, mince up two ounces of onions, two ounces of celery root and two ounces of carrots, and put them into a saucepan with a bunch of parsley, thyme and bay leaf, also one pint of water, some salt and a pint of white wine; let boil for ten minutes. Put three dozen live crawfish into a net, plunge this into boiling water and leave it until the shells turn red, then take it out, and break off the small legs, and finish cooking the fish in the court bouillon for about ten minutes, tossing them well in the meanwhile; remove them with a skimmer and dress them. Strain the broth or court bouillon, reduce it to half, add a piece of fresh butter and pour it over the crawfish.
After the three dozen crawfish have been cooked in the court bouillon, dress them in a silver tureen; strain the court bouillon, reduce it to half with a little brandy and thicken it with kneaded butter and bread-crumbs, season with salt and a dash of cayenne, and incorporate into it a little piece of fresh butter; pour this over the crawfish, toss them well, and strew over some chopped parsley.