1) Cook the pasta in a large pot of boiling salted water until al dente. Drain and return to the pan.
2) Heat the butter in a medium pan over low heat. Add the Parmesan and the cream and bring to a boil, stirring constantly. Reduce the heat and simmer for 10 minutes, or until the sauce has thickened slightly.
3) Add the parsley, and salt and pepper, to taste. Stir well to combine. Add the sauce to warm pasta and toss well to combine.