Score the skin of each ham hock with a sharp knife.
Heat the oil in a large deep pot or Dutch oven over medium-high heat. Add the ham hocks, onions, celery, bell peppers, crushed red pepper flakes, oregano, thyme, and bay leaves and cook, stirring, until the vegetables are softened, about 5 minutes. Stir in the garlic, and cook until fragrant, about 1 minute. Add the stock and bring to a boil over high heat. Reduce the heat to medium-low, cover, and simmer, stirring occasionally, for 1 1/2 hours.
Add the beans and stir. Continue simmering over medium-low heat until the beans are just tender and ham hocks are very tender, 45 minutes to 1 hour. Season with the salt and continue cooking for 15 to 30 minutes, until the beans are tender and the ham hocks are beginning to fall apart. Remove from the heat.
Spoon the ham hocks and beans into bowls (or cut the meat from the bones and stir the meat back into the pot of beans before ladling into bowls) and sprinkle with the green onions and parsley.
Yield: 4 servings