In a large pot, combine the soaked beans, chicken broth, onion, garlic, and oregano. Bring to a boil, then reduce heat and simmer for 45 minutes, or until the beans are tender.
Shred the cooked chicken and add it to the soup. Season with salt and pepper to taste.
Notes
This soup can be made ahead of time and reheated. Leftovers can be stored in the refrigerator for up to 3 days.