Cut the meat coarsely, chop the celery and onions. In a large pot, mix the chopped fillet, celery, onion and pressed garlic. Add the water and crumbled chicken broth cubes.
Bring to a boil and reduce the heat. Cap the dish and boil the soup for 1 hour, removing the foam from time to time.
Add the lemon juice and rice. Boil the soup uncovered until the rice softens. When serving, sprinkle it with finely chopped parsley and spearmint.