Soak the borlotti beans overnight (or at least 8 hours before).Drain the borlotti beans and add to a large pan with water from a recently boiled kettle.Bring to a medium simmer and in the meantime dice the onion, garlic, carrot, kohlrabi, courgette, aubergine and butternut squash and add to the pan with the olive oil.Slice the green beans and add to the rest of the vegetables together with the finely diced basil and saffron, bring to a simmer on a medium heat and cover.After about 30 minutes of cooking add the pasta and gently simmer for another 15 minutes or so.When the pasta and the beans are soft add salt to taste and serve.