Pick up the crabs (= peeling). Hold the head of the crab between thumb and forefinger. With the other thumb and forefinger turn the back end until the shell breaks in the middle. Pull off the end of the shell, pull the crab meat out of the head.
Keep the crab shells. Clean or peel the soup greens, wash them and chop them up. Peel onion, wash tomatoes. Cut both in half. Heat the oil in a large pot. Fry the crab shells, soup greens, onion and tomatoes.
Add 1/8 l wine and 1 l cold water, add bay leaf and peppercorns. Bring to the boil slowly covered and simmer at low heat for about 1 hour. If necessary, skim off the foam that has formed in between.
Pour the stock through a fine sieve.
Peel and finely dice the shallots. Melt butter in a pot. Sauté shallots in it. Dust with flour and sauté lightly while stirring constantly.
Add the stock and 1/8 l wine bit by bit while stirring. Stir in the crab paste. Simmer soup for about 10 minutes. Wash the dill, shake dry and chop finely.
Stir the crème fraîche into the soup. Season to taste with salt, pepper and cognac. Warm the crab meat in the soup only briefly. Sprinkle soup with dill and serve.