- ¼ pound pancetta (or bacon), cut into ½-inch cubes
- 1 medium white or yellow onion, chopped
- ½ cup extra virgin olive oil
- 3 celery stalks, chopped
- 2 cups dried borlotti beans or cranberry beans, covered with cool water, soaked overnight, and drained
- ½ teaspoon baking soda
- Salt and freshly ground black pepper
- A pinch of hot pepper flakes or cayenne pepper
- ¼ cup tomato paste
- 1 tablespoon sugar (or more to taste)
- ½ pound ditalini
- Freshly grated Parmesan cheese
- Place the pancetta in a large pot over medium heat and fry it for about 10 minutes, until it is golden brown and slightly crispy. Add the onions and the olive oil and cook for 10 more minutes, until the onion is soft and light golden.
- Add the celery, drained beans, and 3 quarts of cool water. Bring the water to a boil. Take the pot off the heat to stir in the baking soda.
- Season the soup with salt and pepper and the hot pepper. Be careful not to add too much salt at this point; the water will reduce as you cook the beans and the soup will get saltier as it does. Return the soup to medium-low heat and simmer, uncovered, until the beans are tender, about 2 hours, stirring occasionally.
- Stir in the tomato paste and sugar and simmer the soup for about 10 minutes. Depending on how much water is left and how thick you like your soup, you may need to add some boiling water to the soup. Note that the starch from the pasta will thicken the soup even more.
- Bring the soup to a boil over medium-high heat. Stir in the ditalini and boil the pasta in the soup, stirring very often, until the pasta is tender, about 15 minutes. Serve hot, with grated Parmesan cheese. If you have leftovers, add some boiling water and heat the soup over low heat.