Soup of black beans and pork

Ingredients:
400 g of black beans
100 g onions
100 g of green celery
bay leaf
250 grams of pork with bone
2 liters of water
100 g of chicken broth
salt, black pepper
4 hard-boiled eggs
50 g of parsley
wine vinegar
0.5 lemon

Preparation:
Well-rinsed beans, pour into a large saucepan. Add finely chopped green onions, celery, bay leaf, smoked pork bones. Poured into 2 liters of water over high heat bring to a boil. Remove the foam from the surface, the pan is half closed with a lid, reduce heat to low and simmer the soup for at least 3 hours, until the beans do not soften.Pork bones and bay leaf is removed. Rub the soup through a sieve to form a puree of mass. If he gets too thick, dilute a small amount of chicken broth or water. Add spices to taste, salt, a few dots of black pepper and bring soup to a boil. Just before serving, injected into the soup vinegar and coarsely chopped hard-boiled eggs. For each portion of soup served in a small slice of lemon and sprig of parsley.