Cassava feeds people around the world, and the starch of the nutty tuber, known as tapioca, is made into breads, desserts, and the celebrated pearls in bubble tea. But in the Himalayan region of Dzongu, in Sikkim, India, the Indigenous Lepcha tribe ferments tapioca into alcohol.

“There are around 7,000 Lepchas living in Dzongu,” says Tempa Lepcha, a Lepcha language teacher and curator of the community’s fast-fading traditional practices. “The community has been practicing this art of fermenting and brewing tapioca alcohol for at least a few centuries, if not more.”

More than just a tasty drink, Tunglubuk Chi is offered to the tribe’s animist deity, Kanchenjunga, which is one of the world’s tallest mountains and the source, the Lepcha believe, of their ancestors. It’s commonly served to welcome guests, too, and at marriages and childbirth ceremonies. But few families still brew tapioca alcohol, Lepcha laments. “Making Tunglubuk Chi is a time-consuming and laborious process—people are slowly losing interest in brewing it.” 

Still, Pema Yankee Lepcha harvests the tubers every year in January to make two varieties of  Tunglubuk Chi: red and white. 

“White tapioca is either eaten boiled as snacks or mixed with millet and fermented using marcha, a catalyst made of rice paste and local herbs,” she says. After a week of fermentation, the mix releases a pale-white liquid extract, which is hand pressed, served in a bamboo jug with water, and sipped through a bamboo straw, or pipsin. The resulting beverage is mildly sweet, thick, and warm and relaxing.

Despite its ubiquity, raw cassava can be poisonous. This is true of the red tubers, which the Lepcha soak in river beds for three days to neutralize the toxicity. Peeled, chopped, and boiled, they’re then fermented like white tapioca. 

The millet-tapioca mix left over from fermentation is turned into another beverage: Tunglubuk Arok, a strong-smelling, sweet-bitter, distilled drink that’s more potent than Chi. “A glass can knock you out,” Pema Yankee Lepcha says with a chuckle.