The panino con carciofi alla giudia is built around a texture that almost nothing else in the sandwich world delivers: the shatter of a whole artichoke fried until its leaves go to glass. Carciofi alla giudia is the Roman Jewish quarter's signature preparation, a whole artichoke trimmed, pressed open into a flower, and fried twice, once gently to cook the heart through and once fiercely so the outer leaves crisp into brittle bronze petals while the centre stays tender. The defining fact of the sandwich is that contrast trapped in bread: the heart soft and almost creamy, the leaves snapping like a crisp, two textures from one vegetable that a single fry could never give.
The craft is protecting the shatter, which is fragile and short-lived. The artichoke goes into the bread the moment it is fried and drained, while the leaves are still rigid and audible, because steam is the enemy: a fried artichoke shut into a soft roll sweats and goes leathery within minutes, losing the entire reason it was cooked this way. The bread is chosen to keep its distance, a crusted roll or a piece of pizza bianca with enough structure that it does not slump against the hot vegetable, and it is left dry inside, because a wet condiment would soften the leaves as surely as steam does. The classic build adds almost nothing: a little salt, a squeeze of lemon, perhaps a thread of oil, on the logic that a twice-fried artichoke is a complete thing and anything sauced would erase the crackle. The whole sandwich is a race to eat it before the crisp goes.
The variations are mostly about what is allowed to sit beside the artichoke without dampening it: a few shavings of pecorino romano for salt, a leaf or two of mint, the version on grilled bread rubbed only with garlic. The braised Roman carciofi alla romana, cooked soft in oil and herbs with no fry at all, is a different vegetable preparation entirely. Each is a different cooked artichoke given a loaf, and each deserves its own article rather than being crowded in here.