Bring a large saucepan of salted water to the boil and cook fettuccine according to the packets directions until al dente. With 10 minutes of cooking time left add the butternut squash and cook.
In the meantime oil in a saucepan fry the onion until translucent. Add the mince while stirring, add the rosemary, sage and salt.
In a small saucepan melt the butter then add the flour. Stir for about 1 minute to make a roux. Remove from heat then slowly pour in the milk while stirring constantly. Return to the stove and simmer for a few minutes. Season with nutmeg, salt and pepper.
Drain the pasta and pumpkin. Add the milk sauce to the mince and combine well, stir through the pasta and pumpkin carefully. Sprinkle with freshly ground pepper and serve immediately.