For the soup:
- 1 pound dried pinto beans
- 1 large red bell pepper, diced
- 1 medium onion, diced
- 8 ounces pancetta, small dice
- 4 cups water, plus more for soaking
- 1 (28-ounce) can crushed tomatoes
- 1 tablespoon tomato paste
- 2 bay leaves
- 1 teaspoon dried oregano
- 1 teaspoon dried basil
- 1/2 teaspoon dried thyme
- 1 Parmesan cheese rind (about 2×3 inches, optional)
- 1 cup dried ditalini pasta or small shells
- 1/4 cup fresh thyme leaves, finely chopped
- Shaved Parmesan cheese
- Prepare the beans for an overnight soak by pouring them out onto rimmed baking sheet or plate. Pick out any debris or broken beans. Transfer the beans to a strainer and rinse under cool water. Place the rinsed beans in a large bowl or 6-quart or larger slow cooker if you don’t need to use it overnight (eliminating one extra dish to wash). Add about 6 cups of cool water. Cover and soak overnight, 10 to 12 hours.
- Drain the soaked beans and wipe out the slow cooker insert (if you used it). Return the beans to the slow cooker. Add the 4 cups of water, the bell pepper, onion, pancetta, tomatoes, tomato paste, bay leaves, oregano, basil, dried thyme, and Parmesan rind if using. Give everything a swift, hearty stir to combine. Cover and cook until the beans are tender but not falling apart and the broth around the beans has thickened, 5 to 6 hours on the HIGH setting or 10 to 12 hours on the LOW setting.
- When the soup is ready, bring a large saucepan over water to a boil. Add the pasta and cook according to the package directions, 6 to 8 minutes. Drain the pasta and stir into the soup. Remove the bay leaves and Parmesan rind before serving. Top each bowl with fresh thyme and Parmesan.