Soak rolls in cold water. Wash the asparagus, drain and cut off the woody ends. If necessary, peel the under third of the asparagus spears. Cut off the asparagus heads and put aside.
Cut the remaining asparagus spears into pieces. Wash the chicken fillets, dab dry and cut into pieces. Chop into two portions in the universal chopper. Peel and finely chop the onion. Wash parsley and chervil, dab dry and chop, except for some chervil for garnishing.
Squeeze the bread roll well and knead with the chicken, egg, herbs, a little salt, pepper and half of the onions. Form about 32 small dumplings with moistened hands. Bring the stock to the boil and cook the asparagus heads for 2-3 minutes.
Take them out and add the dumplings to the hot broth. Cover them and let them simmer for about 5 minutes. Take out the dumplings and put them aside. Heat the fat in a saucepan and fry the remaining onion cubes until transparent.
Add the asparagus pieces, steam briefly and deglaze with the hot broth. Bring to the boil, cover and simmer for 10-15 minutes. Puree the asparagus in the stock, stir in crème fraîche and season to taste with salt, pepper and lemon juice.
Put the asparagus heads and dumplings into hot soup and briefly warm them up. Arrange the soup in deep plates and sprinkle generously with the remaining chervil leaves and garnish. Fresh baguette tastes good with it.