In a frying pan, heat 4 tbsp of the olive oil, then gently fry the garlic and chilli for a minute. Add the butternut squash, season with salt and cook for a few minutes until tender and slightly golden.
In a separate frying pan, heat the remaining oil and cook the slices of butternut squash until golden on both sides (about 4-6 minutes). In the meantime, follow the instructions on the pack to cook the tortelloni then drain, reserving a ladleful of the pasta cooking water. Add the pasta to the pan with the diced squash and stir gently, adding some of the pasta water if you need to loosen the sauce.
Divide between two plates, sprinkle with the remaining parsley, top with the slices of squash, and serve.