Pane con lo sfincione is the Palermo move of putting a slab of the city's spongy pizza-bread inside a roll. Sfincione is a thick, soft, deeply risen focaccia-like base topped with a cooked sauce of onion, tomato, and anchovy, scattered with breadcrumbs and shaved caciocavallo, and baked so the crumb stays open and almost wet under the topping. Eaten on its own it is a street square; folded or set into a soft sesame roll it becomes a sandwich of bread inside bread, the airy sfincione doing the work of a filling. The defining note is the topping cooked into that sponge: the slow-sweet onion, the salt of the dissolved anchovy, and the breadcrumb layer that drinks the oil and adds a faint grit against the soft base.
The craft is the sponge, the sauce, and not letting one drown the other. The sfincione dough is proved long and baked thick so the crumb is high and tender enough to soak the topping without collapsing into it, since a base that is too dense reads as heavy and one too slack falls apart in the roll. The onion is cooked down until sweet and the anchovy worked through the sauce until it melts rather than sits as a fillet, so the salt runs all the way through; the breadcrumbs and caciocavallo go on so they crisp and brown slightly in the oven and give the otherwise yielding square a top edge. Set into the roll while still warm, the bread carries that oily, savoury sponge as a single soft mass, and lemon is rarely wanted because the anchovy and onion already balance each other.
The named turns stay on the same Palermo street: the sfincione eaten folded without the roll, and the wider family of the panelle and crocchè rolls and pani câ meusa that share the logic of a baked or fried thing loaded into soft bread. Each of those is a different Palermo street food given the same kind of roll, and each deserves its own article rather than being crowded in here.