- Add the pasta to a pan of boiling water. Bring back to the boil and simmer fast for 9 minutes, stirring now and then. Add the petit pois for the last 5 minutes. Drain and reserve 4tbsp cooking water. Return to the pan.
- While the pasta is cooking, heat the oil and cook the mushrooms, stirring often.
- Add the chives, ham, creme fraiche and mustard to the mushrooms and heat until simmering.
- Season with pepper and simmer for 1 minute. Add to the pasta with the reserved cooking water and toss together. Serve immediately with grated Parmesan and ground black pepper.