In 1191 the Zen monk Eisai 栄西 returned from Song China carrying tea seeds and a method: grind the leaf on stone and whisk it into water, rather than steep it. The book he wrote, Kissa Yōjōki 喫茶養生記, is Japan’s first treatise on tea, and it opens with the sentence that tea is a miraculous medicine for lengthening life. Some of Eisai’s seeds reached the monk Myōe, and from him the fields of Uji. Uji has been matcha’s capital for eight centuries.

The invention that makes matcha matcha is shade. Weeks before harvest, the tea gardens are covered; the leaf, straining toward light, fills itself with chlorophyll and sweet amino acids. This shaded leaf is called tencha 碾茶; its veins are removed, and granite mills grind it, at a pace of mere tens of grams an hour, into a powder fine as silk. A hurried stone runs hot, and a hot stone burns the aroma.

In the sixteenth century, Sen no Rikyū 千利休 built a worldview around this powder: chanoyu, the way of tea. Its four principles still underlie Japanese aesthetics: harmony, respect, purity, tranquility.

The jade froth in your bowl is that inheritance. Eight hundred years, in one sip.