• First soak 1 pound dried beans in salt water: (salt tenderizes them, otherwise you have tough and chewy bean skins). Use one of the following methods:

Use one of the following methods:

Overnight Salt-Soaking,

• Pick through and rinse the beans. For every pound of beans, dissolve 2 Tablespoons salt in 4 quarts cold water. Combine the beans and salt water in a large container and let the beans soak at room temperature for at least 8 hours or up to 24 hours. Drain the beans, discarding the soaking liquid, and rinse well before cooking.

Quick Salt-Soaking Method,

• Pick through and rinse the beans. For every pound of beans, dissolve 3 tablespoons salt in 2 quarts boiling water. Combine the beans and hot salt water in a large pot and let the beans soak at room temperature for 1 hour. Drain the beans, discarding the soaking liquid, and rinse well before cooking.

Make the Soup:

• Heat 2 Tablespoons oil in a 12-inch skillet over medium-high heat until shimmering. Add 6 ounces pancetta and cook until lightly browned and crisp, about 8 minutes. Stir in 3 minced onions, 8 minced garlic cloves and ¼ teaspoon red pepper flakes and cook until onions are softened and lightly browned, 6 to 8 minutes. Stir in 1 cup broth, scraping up browned bits, if any: transfer to slow cooker.
• Stir remaining 3 cups broth, 4 cups water, soaked beans, 1 Parmesan rind (if using), and 2 bay leaves into slow cooker. Cover and cook until beans are tender, 9 to 10 hours on low or 5 to 6 hours on high.

Cook's Reminder:

• Do not add rosemary sprig yet. Adding in at this point will result in overpowering rosemary flavor.
• At end of cooking time, add 1 rosemary sprig, cover, and cook on high until rosemary is fragrant, about 15 minutes. Discard rosemary, bay leaves, and Parmesan rind. Season with salt and pepper to taste and serve with grated Parmesan and additional olive oil, if desired.

Cook's Note:

• At the end of cooking but before you add the Rosemary, if you want more broth, feel free to add up to one cup of water to the soup.