Peel the onion and cut into small cubes. Wash the chives, shake dry and cut into fine rolls. Cut rolls into small cubes.
Melt 40 g clarified butter in a large pan. Roast the bread cubes in it until golden brown and take them out. Melt 1 teaspoon of clarified butter in the pan and sauté the onion in it. Add the chives, except for a little bit for garnishing, at the end. Mix milk and eggs. Grate cheese coarsely.
Mix bread cubes with flour, knead egg milk, cheese and chives-onions and let it rest for about 30 minutes. Form 12 dumplings from the bread roll mixture and put them into boiling salted water. Let dumplings simmer for about 20 minutes at low heat. Bring the stock to the boil. Arrange 3 dumplings each in soup bowls with hot stock and garnish with the remaining chives.