NOTE: If you want to serve these with a raw egg yolk on top for presentation, make sure to serve IMMEDIATELY while the pasta is still very hot and that it's very, very fresh. Have guests break the yolk and stir it well into the hot pasta to integrate it into the sauce. You can omit the egg yolk in the original recipe if you do this, because egg yolks thicken the sauce more and too many can make it too rich.