Peel and halve 2 onions. Peel or clean the vegetables, wash and chop them coarsely. Wash the legs. Boil up everything with peppercorns, laurel, 3 tsp. salt and a good 2 l water. Cover and simmer for about 45 minutes.
Lift the legs out of the stock, drain and allow to cool. Boil the chicken soup from the stock, use the meat of the legs for the chicken salad or as a soup garnish.
For the minced dumplings, wash mint, shake dry and chop. Peel 3 onions and chop finely. Knead 1/3 onion with mint, mince, breadcrumbs, egg, approx. 1 tsp salt and approx. 1/2 tsp pepper. Shape into dumplings.
Heat 2 tablespoons of oil in a frying pan and fry the dumplings for 8-10 minutes.
In the meantime pour chicken stock through a fine sieve. Heat 5 tablespoons of oil in a large pot. Brown the rest of the onions in it. Dust with flour and briefly sauté lightly. Stir in cream and chicken stock, bring to the boil and simmer for about 5 minutes, stirring frequently.
For the crôutons, wash parsley, shake dry and chop. Peel and chop the garlic. Dice bread. Heat 3 tablespoons of oil in a frying pan in cooking fat. Roast the bread in it while turning. Fry parsley and garlic briefly.
Season soup with lemon peel and 4-6 tablespoons lemon juice. If necessary, briefly heat up meatballs again and serve with croutons.