Pizza is a prime example. “Discs of dough topped with ingredients,” as Grandi calls them, were pervasive all over the Mediterranean for centuries: piada, pida, pita, pitta, pizza. But in 1943, when Italian-American soldiers were sent to Sicily and travelled up the Italian peninsula, they wrote home in disbelief: there were no pizzerias. Before the war, Grandi tells me, pizza was only found in a few southern Italian cities, where it was made and eaten in the streets by the lower classes.