Rinse beans in a large pot and remove any debris. Place in a large pot and cover with cold water. Let sit overnight. Drain well.
Cook onion in olive oil until softened, about 5 minutes.
Combine beans, onion, carrot, celery, bay leaf, ham hock, and seasonings in a pot. Add 4 cups chicken broth and 4 cups water, bring to a boil, reduce heat and simmer 1 ½ to 2 hours or until beans are tender.
Discard bay leaf, taste and season with salt and pepper. Garnish with parsley and serve.
