The original recipe for Italian Carbonara is that they are not using any cream but instead they are making cream made of egg yolks and pecorino or parmigiano reggiano cheese. They slowly cook the Guanciale or the pig cheek in low medium fire to make it a little bit crunchy and let the oil comes out from the guanciale that gives the rich taste for the sauce. If the meat is ready they will add a cup of water from the water that they used in cooking the pasta. The starch from the pasta will make the sauce thicken too. It is important also that you turn off the fire when you add the cream so that it will not over cook.
