Boil a few dozen crawfish in a court bouillon with white wine; drain them, and detach the tails from the bodies, suppressing the tail shells. Keep boiling on the side of the fire, one and a half quarts of thickened white soup stock; put into it the crawfish shells after pounding them, and let the soup despumate for thirty-five minutes, remove all the fat, strain and return it to the saucepan; boil it up again, and stir in cayenne pepper to taste. Take all the meat from the tails and claws of the crawfish, chop up the claws with the parings of the tails and claws, mixing in a little bread panada, red butter, a few raw egg-yolks and red pepper; prepare a small forcemeat with this, and shape it into tiny quenelles, rolling them on a floured table; poach them, then drain and put them in the soup tureen with the crawfish tails cut in two lengthwise. Skim the fat from the soup, thicken it with four egg-yolks and two spoonfuls of puree of white asparagus tops, and also a little raw cream; let the thickening cook without boiling, and finish the soup with a piece of good butter working it vigorously with a whip.