Soaking: Place beans in a large pot, cover with 2 quarts of water. Allow beans to soak overnight, or at least 8 hours.
To Cook: Drain soaking water, and add 2 quarts of fresh water, chicken stock or broth and meat. Bring to a rolling boil, reduce the heat and simmer uncovered for 2 to 2-1/2 hours. After simmering, add onions, carrots, celery, tomatoes, chili powder, bay leaf, lemon juice and garlic. Simmer for an additional 30 minutes. Remove bones and bay leaf. Shred meat, return to pot. Salt and pepper to taste.
Cook's Note: Soup freezes well, may need to add more chicken stock when reheating.