Bean Paste Sesame Bun

The precise origins of the bean paste sesame bun are not reliably documented. A story circulated by vendors links it to military rations carried during Prince Zhu Di's Jingnan Campaign (1399–1402), but food historians consider this account a later invention — the source cited for the claim does not appear to exist as a real historical record. What is better attested is the Liu family lineage: starting from a sesame-bun shop on Beijing's Niujie, the family relocated to Tianjin, where successive generations refined the technique into the characteristic form seen today — the dough sealed seam-side out so that bean paste erupts through and sets against the crust during baking. The snack traveled between the two cities along the Grand Canal trade corridor. It is counted among the Thirteen Old Beijing Snacks and carries official Tianjin intangible cultural heritage status, with Liu Ziqing confirmed as the third-generation inheritor.

Still hot from the oven, the exterior gives a satisfying crackle under the teeth — sesame-nutty and lightly caramelized — before giving way to a smooth, almost silky bean paste that is sweet but restrained, with a clean red bean finish. The contrast between the shatteringly crisp shell and the warm, yielding filling is the whole point.

The 'spitting' is a controlled pressure burst: the bun is sealed seam-side out, so when steam pressure from the heating bean paste exceeds the dough's tensile strength at its thinnest point, the paste erupts through the seam and sets in place as baking continues. On the outside, the Maillard reaction between flour amino acids and reducing sugars at 140–170°C produces hundreds of aromatic volatiles — pyrazines, furans, and aldehydes — that create the toasted, nutty crust. Sesame seeds at the same temperature independently release lignans and short-chain fatty acid compounds, adding a distinct nutty aromatic layer.