From what the original article says, authentic ribollita is hard to find. It takes 3 days to prepare. It means "reboiled" and you basically keep re-cooking the leftovers for 2 days after you eat the original meal. Here's the original recipe. I'm going to try it out, and let you know more later.

I thought I'd add to the recipe, and say how to cook the beans. You don't have to use Tuscan white beans, red beans, navy beans, kidney beans, etc are all good substitutes. You don't have to cook the beans this way. I just thought I would add to the recipe below because using dry uncooked beans in the recipe below will not get you the results you want.

Beans

1 bay leaf
1 tbsp salt
water
dry beans

soak in salt water over night. The next day, add more water to the beans until they are covered about an inch. Add the bay leaf, and let the beans boil for about 2-2.5 hours. I like my beans a little on the soft side. If you like your beans harder, boil them for an hour only. Check them periodically until they are the consistency you like. Keep the soup and the beans and use it for the recipe below.

Ribollita

http://www.divinacucina.com/code/ribollita.html

4 tablespoons olive oil
1 red onion, chopped
1 leek, white part only, chopped
1 garlic clove, chopped
4 carrots, sliced into half-inch rounds
4 zucchini, sliced into half-inch rounds
One-quarter whole Savoy cabbage, shredded and chopped
1 bunch cavolo nero or kale
1 small bunch spinach, shredded and chopped
4 potatoes, peeled and cut into one-half inch cubes
1 cup green beans, cut into bite-size pieces
2 cups Tuscan white beans, one-half cup pureed and one-half cup whole
2 tablespoons coarse sea salt or kosher salt
4 tablespoons tomato paste
1 pound stale Italian bread, sliced

Heat the olive oil in a large pot and sauté the onion and leek together over low heat until they begin to burn slightly. Add the garlic and sauté for 1 minute. Add all the remaining vegetables, and the beans. Season with sea salt and stir to mix in the onions and leeks evenly. Cover and cook for 20 minutes or until the vegetables have reduced in volume by half. Stir again and cover with water to the top of the pot. The more water you add, the more broth you will have with the soup. Bring to a boil and then lower the heat. Add the tomato paste and stir to dissolve. Cover and cook the soup for 1 hour.

This is the minestrone soup. The next day layer the soup in a deep baking dish with the stale bread and bake. Top with thinly sliced red onions before baking.

The next day, if there's any soup left over, reboil the soup, stirring well to break up the bread slices. The soup should be thick enough to eat with a fork! It's served with the traditional drizzle of extra virgin olive oil on top.