Yak Butter Tea

Yak butter tea (suyoucha, literally 'crispy-oil tea') is the universal beverage of the Tibetan plateau and one of the functional innovations in high-altitude human nutrition: a hot, calorie-dense, salt-supplementing drink suited to an environment where maintaining body temperature and energy at 3,500-5,000 metres requires more fat and salt than a standard diet provides.

The preparation: coarsely processed black tea (traditionally compressed into bricks from Yunnan or Sichuan) is boiled for an extended period in water, then strained and poured into a cylindrical wooden churn (dongmo) along with a large piece of yak butter, salt, and sometimes a small amount of milk or roasted barley flour (tsampa). The mixture is churned vigorously for several minutes — the fat must emulsify rather than float — until a thick, uniform, oily liquid results. Poured hot into a ceramic bowl.

The flavour is salty, fatty and slightly bitter from the tea, with the specific character of yak butter (richer and more intensely flavoured than cow's butter) dominant. The reaction of those raised on sweet tea is predictably mixed on first encounter. The high-calorie content — one bowl can deliver 100+ calories — explains the daily consumption of many bowls by Tibetans doing physical work at altitude.

Guest etiquette: accept the first bowl offered; drink at least part of it. The host will keep it filled. Refusing the first pour is impolite; declining a refill by covering the cup is the standard signal.