Put the bones in cold water for about 30 minutes to remove the blood, then drain them and put them in cold water to boil. Foam as needed to obtain a clear juice and boil until the meat on the bone is well softened (I use a pressure cooker to reduce the time).
When the bones have boiled enough, turn off the heat and drain the juice through a sieve.
Clean the vegetables, wash them well, then finely chop the onion, and grate the carrot and the white part on a small grater.
First, put the carrot to cook in the hot oil, then add, one by one, the white part and the onion. (This will give the soup a wonderful color). When the vegetables have softened a little, turn off the heat with a ladle of bone broth and let it boil until they are well softened. Add all the beef broth, the fideluta belly and vinegar to taste (1-2 tablespoons). Boil for about 20-30 minutes depending on how soft the belly is. Adjust the salt and pepper to taste and add more water if it is too thick.
In a deep bowl, put the sour cream, egg yolks and chopped garlic. Mix with a fork and pour in a little hot juice with a ladle. Turn off the heat and pour the egg and sour cream mixture into the pot, stirring continuously.
Serve the soup with sour cream, pickled chili peppers and a slice of homemade bread.
12 servings