The panino con carne di cavallo is a Catania street sandwich defined by a meat most of Italy does not eat and Sicily grills with conviction. Horse is lean, dark, faintly sweet, and almost free of marbling, which makes it a difficult thing to cook well and an unmistakable one when it is. In the Catanese version the meat is taken as thin cuts or as salsiccia di cavallo, the horse sausage, and worked over a live charcoal fire until the outside takes char and the inside stays just short of dry. It is then packed hot into a plain roll. The sandwich is a frame for that grilled horse and very little else, because the meat has a strong enough identity that crowding it would only mute it.
The craft is fire management and speed, since a lean meat with no fat to spare punishes a slow cook. The charcoal is run hot so the surface colours fast and the centre is pulled while it still gives, the sweetness of the horse holding against the bitterness of the char. Salt and a little oil go on at the grill; sometimes lemon, sometimes a scrape of salmoriglio, the Sicilian oil-lemon-oregano dressing, to cut the richness without burying it. The bread is a soft, plain roll whose only job is to hold something hot and just off the coals; it is filled the moment the meat comes off and eaten standing, because horse this lean stiffens as it cools and the sandwich does not improve with waiting.
The variations stay within the Catanese fire tradition and the wider Sicilian one. There is the sausage build and the build of thin grilled cuts; there is the version dressed with grilled onion or with the city's bitter greens worked in alongside the meat. Raw horse preparations exist elsewhere and follow an entirely different logic, and the broader family of place-named Sicilian grill panini sits beside this one rather than inside it. Each of those deserves its own article rather than being crowded in here.