The panino con quarume is a Palermo street roll built around simmered tripe and innards, and the thing that defines it is the pot rather than the bread. Quarume is a long-cooked broth of mixed bovine offal, the stomach chambers and lengths of intestine cleaned and boiled for hours with carrot, celery, and onion until the connective tissue gives and the broth turns rich. The pieces are lifted from the liquor, cut, and packed hot into a soft roll. This is a different organ argument from pani câ meusa, the Palermo spleen-and-lung roll dipped in lard: quarume is a wet, brothy tripe build, not a fried-and-glossed one, and the two stalls sit side by side without overlapping.
The craft is in the cleaning, the simmer, and the broth carried to the roll. The offal is the part most cooks get wrong, since it has to be scrubbed and blanched until there is no off note left, then cooked slowly so the tripe goes tender without turning to rags. The broth seasons everything, so a ladle of it is spooned over the meat in the roll and the bread is allowed to drink some of it, eaten at the point where it is saturated but still holds. A squeeze of lemon and a hard grind of black pepper are worked in at the counter; salt is adjusted there too, because the pot is the seasoning and the roll only carries it. The bread is plain and soft on purpose, a vehicle for something hot and brothy that has been cooking since morning.
The variations stay narrow and Palermitan, each its own preparation rather than a footnote here: the bowl version eaten as quarume in broth with the bread alongside rather than stuffed; the mixed offal stall that runs quarume next to stigghiola and musso; and the lemon-and-pepper dressing taken heavier or lighter by stall. Each is the same simmered-innards-and-broth logic given a roll, and each deserves its own article rather than being crowded in here.