The erbazzone is the savoury baked pastry of Reggio Emilia, and it sits in this catalogue on the strength of how it is actually eaten: cut into a square or a wedge, held in the hand, folded slightly, and bitten into like a closed sandwich. It is a thin lardy crust enclosing a dense filling of Swiss chard, or chard and spinach, bound with a heavy quantity of Parmigiano-Reggiano and softened with sautéed onion and strutto, the local lard. There is no second component and no dressing: the dish is its own enclosed thing, a pastry that happens to behave like bread around a filling, and the Reggiano larder is the entire flavour.
The craft is the crust and the bind. The pastry is rolled thin, sometimes brushed with more lard and laid in two sheets, top and bottom, so it bakes to something between flaky and short rather than rich and tall. The chard is wilted hard and squeezed dry before it goes in, because a wet greens filling steams the base soft and the whole point of the erbazzone is a firm slab that holds a clean edge when cut. The Parmigiano is not a seasoning here, it is structural: enough of it sets the filling so a square stays intact in the hand and reads as a single dense layer rather than a loose pile of greens. Browned onion and the lard carry the salt and the fat, and nothing else is added because the cheese and the chard are the statement.
The variations are local and few, and the wider family keeps its own pages. There is a thicker, taller version closer to a pie, the so-called erbazzone montanaro with rice or a richer crust, and the broader Emilian habit of folding split or fried breads around the same cured-meat and soft-cheese shelf. Each is a different baked or griddled vehicle for the Reggiano and Modenese pantry, and each deserves its own article rather than being crowded in here.