Preparation

1. Soak the mushrooms in the wine over night. 
2. Drain mushrooms and save the wine for the sauce. 
3. Heat the olive oil and butter in a pan, sautee slowly the mushrooms, garlic, rosemary, salt and pepper. 
4. Pour in the veg stock, wine and cream then simmer on a very low heat for about 5 mins, stirring frequently.
5. Bring a large saucepan of water to the boil, add the salt and the pasta, bring back to the boil and cook according to manufactures suggested cooking time. 
6. Check a few minutes before cooking time is up, the pasta should be served al dente, firm on the inside yet soft on the outside.
7. Drain in to a sieve, mix with the sauce, drizzle with truffle oil, sprinkle on the parsley and serve immediately.
8. Add parmesan if desired. The sauce can be made one day in advance if chilled then reheated thoroughly.