Tigelle con cunza is the foundational Modenese version, the one where the dressing is the whole argument. The tigella, properly the crescentina, is a small leavened disc cooked between two patterned plates of a tigelliera until it sets pale and faintly freckled, firm enough to hold its shape but soft enough to tear open along its equator. Cunza, also called pesto modenese, is a paste of lard pounded with garlic and rosemary, often sharpened with a little grated Parmigiano. It is smeared into the disc while the bread is still hot off the iron so the fat slackens, melts into the warm crumb, and slicks it through. The two need each other exactly: a plain split disc is bland leavened bread, and cunza on its own is a spoonful of seasoned lard. Together the warmth releases the garlic and rosemary into a savoury fat that the bread absorbs, and that is the entire dish before any meat is even considered.
The craft is in heat and in the pounding. The disc must be small so it stays warm long enough to be split and dressed at the table, because cunza only works while the bread can melt it; smeared into a cold tigella the lard stays waxy and the whole point is lost. The paste itself is pounded, not chopped, so the garlic and rosemary disperse evenly through the fat rather than landing in hot pockets, and the lard is good and clean because there is nowhere for an off note to hide. A correct build keeps the dough deliberately plain so it carries the fat without arguing, and applies the cunza in a thin even film rather than a greasy slab. A sloppy version uses a cold disc, a coarse lard with raw garlic chunks, or so much paste that it weeps out the seam and turns slick instead of savoury.
The variations are all the same warm split disc met by a different filling, and each is its own article. There is the version where cunza is the base and cured meat or a soft cheese is added on top of it, the plainer one finished only with Parmigiano, the disc dressed instead with whole lardo, and the fully loaded salumi misti build. There is also the sweet end-of-meal habit of a warm disc with Nutella or jam for children. Each changes what meets the bread while the iron and the seam stay constant, and each deserves its own article rather than being crowded in here.