1 18 ounce jar diced tomatoes with juice (I like Jovial)
1 pound dried cranberry beans (aka Borlotti beans), soaked at least 6 hours or overnight and drained (I prefer Rancho Gordo), or use pinto beans
Large piece of rind from a wedge of Parmigiano-Reggiano cheese (if you have it)
8 cups of water, or homemade chicken or vegetable stock
3 cups baby spinach leaves or chopped Swiss chard leaves
2 teaspoons sea salt or more if using unsalted stock or water
Freshly ground black pepper to taste
Sliced basil leaves or pesto for garnish (optional)
Freshly grated Parmigiano-Reggiano or Pecorino-Romano cheese (optional)
Instructions
Heat the olive oil over medium-low heat in a large pot and add the onions, garlic, carrots and celery. Cook until vegetables have softened and the onions are tender and translucent, about 8 minutes.
Add the tomatoes with the juice and cook for 5 more minutes, until the tomatoes are fragrant.
Add the drained beans, Parmesan rind and water or stock (do NOT add salt here) and bring to a boil. Lower the heat and simmer, partially covered for 1 hour, or until the beans are tender. Softening the beans can take anywhere from 1 to 2 hours, depending on the age of the beans.
Once the beans are softened, add the spinach and stir until wilted.
Add the salt and pepper and taste for seasoning. Top with sliced basil leaves or pesto and grated cheese (if desired).