A classic example of the simple and flavorful cucina povera* (poor cooking), this "re-boiled" soup uses day-old bread and a wide array of seasonal produce (think: swiss chard, leeks, carrots, or whatever you hav in your fridge). As the flavors blend, this soup only gets tastier over a couple of days, making it the perfect weekday or weekend dinner(s)!
Place the olive oil, onion, and garlic in a pot over medium heat. Cook, stirring frequently, until the onions and garlic are soft, about 5 minutes.
Add the carrots and celery, and cook, stirring frequently, until the vegetables have softened but not browned, about 8 minutes.
Add the zucchini and cook, stirring, until softened, about 8 more minutes.
At this stage, add the kale, and cook – keep stirring – until the greens are very soft, about 8 minutes.
Add the tomatoes and their juice, break up the tomatoes with a wooden spoon in the pot. Add 2 quarts of water, the bay leaf, the thyme, and beans. Season to taste with salt.
Bring to a boil, and then reduce the heat to a simmer. Cook until the vegetables are very tender, about 30 minutes. Remove and discard the bay leaf.
Add the bread cubes and parmigiano to the soup, and simmer until the bread is breaking apart and the soup is very thick, about 10 minutes.
Remove from heat and let the soup rest for several minutes, and then ladle into warmed bowls. Drizzle a generous amount of extra virgin olive oil over each portion before serving. Optional: sprinkle a few red pepper flakes for extra heat.
Notes
Use day-old rustic bread so it properly absorbs the broth and creates the signature thick, stew-like texture
Build a strong flavor base by slowly sautéing onions, carrots, and celery until soft and fragrant before adding liquids
Finish with good olive oil and Parmesan for richness and an authentic Tuscan finish