Heat the oil in a pan. Fry the mushrooms in batches, remove. Sauté the onion, garlic and squash in the same pan for approx. 5 mins. Pour in the stock, bring to the boil, reduce the heat. Cover the sauce and simmer for approx. 15 mins. Pour in the cream, bring to the boil, season. Return the mushrooms to the pan.
Cook the pasta in salted water until al dente, drain. Plate up the pasta and sauce, garnish with parsley.