Place the beans in a large saucepan and cover with cold water by about 2 inches. Bring to a boil and lower the heat to a simmer. Cook for 5 minutes; remove from the heat, cover, and let sit for one hour. Drain and reserve. Tie the parsley, thyme, and bay leaf together with kitchen twine.

In a large soup pot or Dutch oven combine the beans, herb bundle, hocks, onions, and garlic with the water. Bring to a boil, cover, and adjust the heat so the soup cooks at a gentle simmer. Cook until the beans and hock are completely tender, about 1-1/2 hours.

Turn off the heat and remove the hocks. Cool slightly. Remove the meat from the hocks, discarding the bones, fat, and skin. Cut the meat into small cubes. Remove the herb bundle and discard.

Puree about 3 cups of the beans with a some of the liquid in a blender. (For a smoother soup puree all the beans.) Stir the puree and diced meat into the soup. Heat the soup and adjust the seasoning as needed with salt and pepper.

Pour into heated bowls, place a small pat of butter on top of each soup, and serve.