This pasta is from the region of Lazio, around Rome. Some sources believe the dish was developed at the end of World War II, when American soldiers stationed in Rome brought rations of eggs and bacon to Italian friends who turned them into this pasta sauce. Other sources suggest that it originated with coal miners (carbonari) in the region. It may be made with either pancetta or guanciale. Both are cured pork products: Pancetta is made from the pork belly, guanciale from pork jowl.