2 thyme sprigs, leaves picked, plus extra to serve
Heat the oil in a non-stick frying pan over a medium heat, then add the swede, onion and garlic and fry for 5 mins. Cover with a lid and cook for a further 10-15 mins, stirring so it doesn’t stick, until the swede is completely soft. Set aside to cool, then blitz in a food processor or mash with the parmesan and a large pinch of seasoning. Add a splash of water to loosen the sauce.
Cook the pasta in salted water for 1 min less than pack instructions, reserving a little of the cooking water. Meanwhile, use the frying pan you used for the sauce to fry the pancetta until crisp, around 5 mins. Add the thyme and fry for 1 min, then tip into the sauce.
Using tongs, transfer the pasta to the sauce, add the reserved water, and give everything a good toss around the pan, so the pasta is well coated in the sauce. Season, then split between bowls, top with more parmesan and a big grind of black pepper to serve.