Cōngyóubǐng (葱油饼) is the scallion oil pancake, a coil of oiled, scallion-laced dough rolled flat and pan-fried until the layers separate into crisp, flaky leaves. The angle is lamination. This is a flatbread engineered to have hundreds of thin sheets of dough divided by film of oil and flecks of green, and the entire craft is building that internal structure so the finished round shatters and pulls apart rather than chewing like a tough disc. Get it right and the outside is golden and brittle while the inside stays in tender, distinct layers shot through with scallion; get it wrong and you get a dense, greasy, bready slab with the scallion sitting on the surface doing nothing.
The build is a rolled and coiled lamination, not a simple flat round. A soft wheat dough is rested until relaxed, then rolled out thin, brushed generously with oil or rendered fat, and showered with finely chopped scallion and salt. The sheet is then rolled into a long rope, which is wound into a tight spiral and pressed or rolled flat again, a move that stacks the oiled, scallion-filled layers on top of one another. The disc goes into a hot, lightly oiled pan and is fried on both faces, often pressed and flipped repeatedly, until it is deeply browned and the layers puff and crisp. A final move some cooks use is to fluff the cooked pancake by clapping it from the edges so the leaves loosen and separate. Good execution shows a round that is crackling and blistered outside, clearly layered inside, well salted, and not heavy with grease; the scallion should be cooked into the dough, sweet rather than raw and harsh. Sloppy work is easy to spot: dough rolled without enough oil so it fuses into one bready mass, a pan too cool so the bread soaks fat and turns leaden, or scallion added so coarsely that it scorches and turns the layers bitter.
It shifts mostly by thickness, fat, and what it is paired with. A thin, crisp version reads almost like a cracker; a thicker, chewier one is closer to a soft layered bread. Lard gives the most tender, flaky result, while plain oil makes a lighter, crisper one. The pancake is eaten on its own, torn and dipped, or pressed back into service as a wrapper folded around egg, meat, or pickles, builds that get their own treatment. What keeps cōngyóubǐng its own entry is the coiled lamination and the scallion cooked into the layers, the feature that separates it from a plain griddled flatbread.