Sort the beans, then rinse with cold water. Place the beans in the large bowl, cover with water plus two inches. Soak overnight.
Place one tablespoon of olive oil In a 5-quart Dutch oven, saute celery, onion, green peppers, sausage, and garlic over medium heat until slightly brown.
Add beans, soaking liquid, ham hock, bay leaf, cayenne, cumin to the dutch oven. Additional water if necessary.
Simmer for several hours until the beans are soft.
Serve over hot fluffy rice. Top with sliced green onions.