Consuming undercooked eggs may increase your risk of foodborne illness. If you are uncomfortable serving egg yolks at the table, you can stir the egg yolks into the pasta in the skillet to heat them through. The smoked mozzarella in this recipe is reminiscent of the bacon traditionally used in carbonara; if you can't find it, use traditional mozzarella or substitute Parmesan (using 1 cup Parmesan total).