I use slab bacon here because I like large pieces that are brown on the outside but still moist in the center. If you cannot find slab bacon, use the thickest-sliced supermarket bacon you can find. Just be sure not to overcook it. If you prefer, you can pour off all the bacon fat after browning the bacon and replace it with an equal amount of olive oil, but remember, the bacon fat has a much more pronounced flavor. If you don’t have the stock called for in the recipe, just use water from the pasta pot. Often you will see this dish prepared with cream. It’s not the traditional style, but that’s not to say it doesn’t taste good. But I prefer my carbonara made this way, the sauce thickened lightly with egg yolk. The heat of the pasta is enough to cook the egg yolks, but if you like, you may bring a small saucepan of boiling water to a simmer and, about a minute before draining the pasta, slip the yolks into a small sieve placed in the simmering water, to coddle them for a minute. Carefully lift the sieve from the water and add the coddled yolks to the pasta as described below.
The Importance of Coarsely Ground Pepper: Coarsely ground black pepper is essential to this dish. If your mill doesn’t grind pepper coarsely, try the following trick: Place the peppercorns on a flat surface. Holding the rim of a small, heavy saucepan or skillet with one hand, and pressing down on the center of the pan with the other, crush the peppercorns until coarsely ground.
