1.Soak the beans overnight and then cook over low heat. It will take approximately 1 to 1 1/2 hours for them to cook.
2.In a pan, gently fry the onion. Add the other vegetables, with the exception of the cabbage, kale and beans which are added at a later point. When the vegetables have sweated out their juice, cover with hot water and then add all the cabbage and kale. Cover and simmer for an hour over medium heat.
3.Add the cooked beans (some of them whole and some puréed), salt and pepper. Leave to simmer for another 20 minutes, stirring frequently because the beans tend to stick to the bottom of the pan. Add the tomato paste.
4.Slice the stale bread and, in an earthenware casserole, alternate layers of bread with the soup until the bread is soaked. Let rest for one day.
5.To serve, remove the desired quantity from the casserole and reheat it, or "re-boil" it, as the name in Italian suggests