Put the borlotti beans in a large bowl, cover with cold water and leave to soak overnight. Drain and rinse under cold water.
Melt the butter in a large saucepan and add the onion, garlic, parsley, sage and pancetta to make a ‘sofrito’. Cook over low heat, stirring once or twice, for about 10 minutes, or until the onion is soft and golden.
Add the celery, carrot and potatoes and cook for 5 minutes. Stir in the tomato paste, tomatoes, basil and borlotti beans. Season with plenty of freshly ground black pepper. Add the stock and bring slowly to the boil. Cover and leave to simmer for 2 hours, stirring once or twice.
If the potatoes haven’t already broken up, roughly crush them with a fork against the side of the pan. Taste for seasoning and add the zucchini, peas, beans, cabbage and pasta. Simmer until the pasta is al dente. Serve with a dollop of pesto and the parmesan.