Step 1The day before making the soup, place the beans in a nonreactive pot with enough water to cover the beans by 2 inches. Soak the beans overnight.
Step 2The next day, add the onion, celery, tomatoes, garlic, herbes de Provence and bay leaves to the pot with the beans and soaking liquid (add additional water as needed to keep the beans submerged). Simmer the soup until the beans are tender, stirring occasionally and adding additional water, if needed, to keep the beans submerged.
Step 3While the soup is cooking, render the bacon in a separate pot until crisp. Stir in the diced ham and remove from heat.
Step 4When the beans are tender, stir in the bacon and ham, along with the rendered bacon fat. Add additional water if desired to thin, and season with 2 teaspoons salt and 1 teaspoon pepper, or to taste. This makes a generous 4 quarts soup.