Gambero Rosso Carbonara choices?
I live in Rome and have very strong feelings about guanciale! It differs from pancetta (more fat, harder texture, taste totally different) and is the thing to use in anything originating from Rome/Lazio, ie. Amatriciana, Carbonara and Gricia, (Say also all Romans I know) so in a Roman restaurant, it would be a sign of tradition and quality.
That said, I am aware that outside of Italy (even within Italy, outside of Lazio), it can be hard to get guanciale, so you will have to make do with pancetta or even bacon for the most unfortunate.
And: A carbonara consists of pasta (in Rome most of the time rigatoni), egg(s), cheese, guanciale, blackpepper and oliveoil. The discussion in Rome is along the lines "egg, egg plus eggyolk or two eggs?" or "only pecorino Romano or some Parmiggiano mixed in?"... Never ever cream, milk or other stuff..... Everytime I read about a "carbonara" recipe on the internet (mostly blogs) I am cringing!