Meanwhile, heat the olive oil in a large enameled cast-iron casserole. Add the pancetta and cook over low heat until golden, about 5 minutes. Add the onion, leek, garlic, celery and carrots and cook, stirring, for 3 minutes. Add the stock, thyme, bay leaves, sage and Parmesan rind and simmer for 5 minutes. Add the cabbage, kale, tomatoes and their juices and the cooked beans and their liquid. Cover and simmer for 45 minutes. Add the green beans, cover and continue to simmer for 1 hour. Discard the thyme sprigs, bay leaves, sage and Parmesan rind. Season with salt and pepper and remove from the heat. Serve in bowls. Pass the hot sauce.