Sua Dau Nanh

Soy milk reached Vietnam through its long contact with Chinese food culture, where ground-soybean drinks are ancient, and it settled into Vietnamese street life as a cheap, nourishing everyday drink rather than a dish with a fixed origin. The Vietnamese signature is the pandan leaf, whose grassy-vanilla aroma turns plain soy milk faintly floral and green — a southern-Asian flourish not found in the Chinese original. Đà Lạt, the French-built hill station whose cool evenings suit a hot drink, became particularly known for its sữa đậu nành vendors, several of them long-running family stalls clustered around the central market.

Hot, the glass steams and smells of warm bean and a clean green pandan note; the texture is light-bodied and silky, never chalky if it has been ground and strained well. Iced, it comes thicker and sweeter over a tall glass of ice. The flavour is gently nutty and mild, the sweetness restrained, the pandan more aroma than taste. A proper Vietnamese soy milk has no raw 'beany' bitterness — that has been boiled out — and slips down clean and faintly sweet, comforting rather than rich.

Dried soybeans are soaked until swollen, ground with water into a slurry, and the raw milk squeezed out through cloth, leaving the okara pulp behind. The crucial step is the boil: raw soy milk contains trypsin inhibitors and a beany-tasting enzyme (lipoxygenase) that thorough boiling deactivates, which is what removes the raw bitterness and makes it digestible — undercooked soy milk tastes grassy-bitter and can upset the stomach. Pandan leaves are knotted and simmered in for the last stretch so their volatile aroma infuses without cooking off, and sugar is added off the heat to taste.