Knead the ground pork, egg yolk and 1 teaspoon of flour. Form approx. 20 small dumplings with moistened hands. Bring a good 1/2 litre of water to the boil and let the meatballs simmer at low heat for about 4 minutes.
Remove with a skimmer and place on a plate. Stir the stock into the hot cooking water. Peel and finely chop the shallot. Wash the herbs, dab dry. Put some chervil leaves aside for garnishing.
Chop the parsley and the rest of the chervil, cut the chives into fine rolls. Heat the fat in a pot and sauté the shallot in it until transparent. Add the rest of the flour, sauté and pour on the stock while stirring.
Add cream, bring to the boil and simmer for about 4 minutes. Add herbs, up to about 1 tablespoon, and continue to simmer for about 1 minute. Puree the herbs with a chopping stick. Add meatballs to the hot soup.
Season to taste with pepper and possibly a little salt or broth. Arrange the soup in deep plates and serve sprinkled with remaining chopped herbs and chervil leaves.