I just found this marvelous spice database entry on cassia that launches unexpectedly into a minor treatise on Chinese cooking techniques.

It makes me very hungry. I want to make a shui lu (or is it lu shui?).

Typical flavourings for a master sauce are rice wine, fresh ginger and basically all the spices employed for red braising: Cassia, star anise, orange peel, fennel, sichuan pepper and licorice. Sichuan cooks will often use additional spices like black cardamom and lesser galangale. Mixtures of whole spices for master sauces are often sold as lu shui liao [鹵水料] “grains for master sauce”.

The master sauce is not served; it may be diluted with fresh broth, rice wine and soy sauce and re-used. To keep it from spoiling, it should be reused or at least brought to a short boil every day, which is indeed possible only in a restaurant; in Western households, it is much more convenient to keep it in the freezer till next usage. The more often the master sauce is used, the more aromatic and “masterly” it tastes.

On the site, all those spice names are linked. I've just started growing some galangal....

...and here's a blog with a recipe for lu shui dan, or tea eggs. Hard boiled eggs, cracked, and cooked again in a marinade made from anise seeds, soy sauce and ordinary black tea.

...and there's another lu shui recipe up here,with amounts of ingredients and stuff.

I *really* need to get some Sichuan pepper.