Bring a large pot of salted water to a boil.
Add the fettuccine pasta and cook according to package instructions until al dente.
In a saucepan, melt the butter over medium heat.
Add the heavy cream and stir gently.
Grate the Parmesan cheese and add it to the cream mixture.
Season with salt and black pepper to taste.
Drain the pasta, reserving a bit of pasta water.
Combine the pasta with the sauce, adding a bit of reserved water if needed.
Thinly slice the fresh truffles and fold them into the pasta.
Serve immediately, garnished with chopped parsley.