Roast some chopped white roots with peppercorns, cumin and parsley in 100 g of butter, add the crayfish with a splash of water so that the steam kills them immediately, let the water content evaporate, add rice, some salt and a little tomato paste and, after roasting for a short time, deglaze with brandy or cognac and then add 1 1/4 l of water. After boiling, remove the crayfish from their shells, one part of which is pounded with 50 g of butter and roasted, while the rest is added to the boiling soup. After the butter of the roasted crab shells has foamed up, it is poured with water, boiled and chilled so that the pink crab butter can be neatly lifted off and put into a small snow basin. Once the rice and roots are completely soft, strain the soup through a fine sieve, squeeze it well and beat it with the fresh cream in a boiling water bath. Stir the resulting crab butter with 2 egg yolks, beat it on medium-hot water until it thickens, and then beat it with the finished soup in a water bath, stirring constantly. As a garnish serve the detached crab tails and claws, vegetable flavors and small peeled tomatoes.