Around the U.S., hundreds of pizzerias offer regular or Sicilian-style slices – the latter having more of a focaccia-like texture. The square-shaped slice features a thick dough, usually covered with cheese and tomato sauce, and, like a standard triangular slice, can hold toppings. This pizza most refer to as “Sicilian” is actually derived from sfincione, a street food synonymous with Palermo, Sicily's capital.
Nowadays, it's topped with tomato sauce, but the original version was complete with anchovies, sliced tuma (Sicilian cheese made from raw sheep’s milk), breadcrumbs with grated pecorino cheese, onions, salt, and extra-virgin olive oil. It originated in Bagheria, a town in the commune of Palermo that's around six miles from the city center. In fact, sfioncione was a Christmas go-to well before panettone came along.