Master Stock (Lu Shui)

Origin: China. A soy-sauce-and-spice braising liquid — typically star anise, cinnamon, ginger, and rock sugar in a soy base — that is strained and reused repeatedly over months or years, deepening in flavor with each use.

Flavor Profile: Deeply savory-sweet and aromatic, with the accumulated flavor of everything previously braised in it layered into the base.

Culinary Uses: Braising liquid for lu wei (soy-braised meats, eggs, and tofu); reused continuously as a prized, ever-improving kitchen asset in many Chinese households and restaurants.

Regional Variations: Regional variation exists mainly in the spice ratio and whether Shaoxing wine is included; some family master stocks are decades old and treated as heirlooms.

Storage: Strain after each use and refrigerate or freeze between uses; properly maintained (reboiled periodically), a master stock can theoretically last indefinitely.

Notes: A structural outlier among stocks — its defining feature is continuous reuse and flavour accumulation rather than being made fresh each time.