How to cook
The chicken is deboned and cut into pieces. Place the bones from the chicken in a deep pot and cover them with 8 1/3 cups (2 liters) of cold water. The celery, carrots, parsley and onions are finely chopped and added to the pot.
Add some black pepper peppercorns and boil. The potatoes and tomatoes are cut into small pieces and added to the pot along with the rice.
The yolk is whisked with the yoghurt. Pour 1 ladle of broth in, stir and thicken the soup.