Hearty Tuscan Bean Stew

1 lb. dried cannellini (2 cups), picked over and rinsed

1 Tbsp. extra-virgin olive oil

6 oz. pancetta, cut into ¼" pieces (you can substitute bacon)

1 lg. onion, chopped medium (1½ cups)

2 med. celery ribs, cut into ½" pieces (3/4 cup)

2 med. carrots, peeled and cut into ½" pieces (1 cup)

8 med. garlic cloves, minced

4 cups low-sodium chicken broth

3 cups water

2 bay leaves

1 bunch spinach, kale, or collard greens (1 lb), chopped into 1" pieces

1 14.5 oz. can diced tomatoes, drained and rinsed

1 sprig fresh rosemary

freshly ground black pepper

Dissolve 3 Tbsp. salt in 4 quarts of cold water. Add beans and soak at room temperature for at least 8 hours and up to 24. Drain and rinse well.
Preheat oven to 250 degrees and adjust rack to lower middle position.
Heat oil and in a Dutch oven over medium heat, then add the pancetta (or bacon) stirring occasionally. Cook until pancetta is light brown and the fat has rendered, about 6-10 minutes.
Add onions, celery, and carrots. Cook, stirring occasionally, until the vegetables have softened and are lightly browned, 10-15 minutes. Stir in the garlic and cook until it is fragrant, about a minute. Stir in the broth, water, bay leaves, and beans. Increase heat to high and and when it reaches a simmer, cover the pot and place it in the oven. Cook until the beans are almost tender, 45-60 minutes. The very center of the beans should still be firm.
Remove from oven. Stir in the greens and tomatoes. Cover and return to oven and cook until the beans and greens are fully tender, 30-40 minutes longer.
Remove from oven and immerse the rosemary sprig in the stew. Cover and let sit for 15 minutes. Discard rosemary and bay leaves. Adjust seasoning with salt and black pepper.