Bring a large pan of salted water to the boil for the pasta. Melt the butter in a large, deep frying pan, add the bacon and cook over a medium heat for a few minutes, until golden brown.

Add the pasta to the boiling salted water, stir and return to a gentle rolling boil. Cook for 8 minutes until al dente. Meanwhile, in a bowl large enough to hold the pasta, mix together the egg yolks, cream, Parmesan, pepper, nutmeg and parsley

Drain the pasta. Remove the bacon from the heat and add the pasta to it, mixing quickly with the bacon and butter.

Add the pasta mixture to the egg mixture and toss well. The heat from the bacon, butter and pasta will cook the egg yolks.