Huangshan Shaobing

The shaobing belongs to the baked-pastry tradition of old Huizhou (Shexian and the surrounding hills, today's Huangshan municipality in southern Anhui). Its compact size and long keeping made it a staple in the packs of the Huizhou merchants (徽商) who fanned out across the country from the Ming and Qing dynasties, so it spread well beyond its home counties. Several names attach to it: 蟹壳黄 from the crab-shell colour the charcoal gives the crust, and the honorific names 救驾烧饼 and 皇印烧饼 from folk tales — that the future Ming founder Zhu Yuanzhang ate it as army rations while in hiding, and that the Qing Qianlong emperor praised it on a southern tour and bestowed the 'imperial seal' name. These imperial stories are folklore rather than documented record; the dish's real identity is as Huizhou merchant road food. The filling of dried mustard greens and pork fat is itself characteristic of Huizhou home cooking, where 梅干菜 is a year-round preserve.

A good shaobing shatters the instant you bite it: the crust breaks into dozens of thin, brittle leaves that flake down your front, and the sesame on top toasts to a nutty fragrance. Inside, the dried mustard greens are dark and savory-sweet, slicked by the melted pork fat so the filling tastes rich rather than dry, with a faint smokiness from the charcoal. Fresh from the oven the aroma is strong and the leaves are at their crispest. A poorly made one is heavy and bread-like instead of flaky, the layers never having separated; or the fat is stingy and the filling turns dry and salty; or it is baked pale and tastes of raw flour rather than toasted crust.

The flakiness comes from laminating two doughs. A water-and-oil dough (flour, water, and lard) is wrapped around a dry short paste (flour kneaded with lard alone), then rolled and folded so the fat separates the dough into many thin sheets; in the oven the water in the sheets flashes to steam and pushes the leaves apart while the lard waterproofs and crisps each one, giving the shattering layers. Lard works better than vegetable oil here because its solid fat coats the flour and blocks gluten from forming a tough, bready crumb. The malt-sugar wash browns the surface through caramelization and the Maillard reaction, deepening it to the crab-shell colour and helping the sesame stick and toast. The diced pork fat in the filling renders during baking, basting the dried mustard greens from inside so they stay moist and carry flavour. Baking is done against the hot inner wall of a charcoal oven: the cakes are stuck to the wall, baked, then finished by the oven's residual heat after the flames die down, a slow bake of several hours that dries the layers crisp without scorching.