1. Cook the fettuccine according to packet directions. Strain and save half a cup of cooking liquid.
  2. In the meantime, heat a heavy-based frying pan on medium heat. Add the butter and half the cream. Simmer for about one minute.
  3. Transfer the strained fettuccine to the frying pan and add the rest of the cream, mixing thoroughly.
  4. Add the cheese and parsley and continue to mix, maintaining the moderate heat.
  5. Add a little of the cooking liquid if the pasta becomes too dry.
  6. Serve immediately.