In a non-stick pan, sweat finely sliced onions. Add chopped radicchio and cook for 5 minutes, adding half a glass Riesling, if necessary. In another pan, heat crescenza cheese on a low heat, add Parmesan and stir. Add the onion and radicchio mixture.
Add salt and black pepper as required, and cook for about two minutes. Boil Aliveris Fusilli in salted water and cook for 10 minutes maximum. Drain pasta and add the sauce.
Serve with some extra Parmesan cheese or between two puff pastry discs. If you prefer the latter idea, heat the oven at 180°; in the meanwhile cut one disc of puff pastry dough for each portion. Bake for 10 minutes; let the discs cool down and cut horizontally, so you can stuff with Aliveris Fusilli.