Glutinous rice is the staple grain of Isaan (northeastern Thailand), northern Thailand, Laos, and much of inland mainland Southeast Asia. It is a different culinary tradition from the jasmine rice of central Thailand — and its manner of eating (pressed into balls with the right hand and used to scoop other dishes) reflects its different texture. Thompson covers glutinous rice extensively because its preparation method is so frequently misunderstood by cooks from outside the Isaan tradition.
Glutinous rice — called sticky rice (khao niew) in Isaan and northern Thai — is a different grain from jasmine rice, with a different starch structure (almost entirely amylopectin, the branching starch, rather than the amylose-amylopectin combination of other rices) that produces its characteristic cohesive, slightly chewy texture. Glutinous rice is not cooked by absorption — it is soaked overnight and then steamed. The soaking hydrates the grain sufficiently that steam alone can cook it without boiling water. Any attempt to cook glutinous rice by absorption produces an unevenly cooked, clumped, gluey result. The 8-hour soak is not optional.
**The soak:** Rinse the glutinous rice (no ritual here — just once or twice). Cover with cold water by at least 5cm. Soak for minimum 8 hours, or overnight. The soaked rice will have swollen and the grains will be translucent. Under-soaked rice does not cook through evenly in the steamer and the centre of each grain remains chalky. **The steam:** Traditional equipment: a cone-shaped wicker basket (a huad) that fits inside a metal pot (a maw neng) with a water-boiling base. The basket holds the rice above the boiling water; the steam rises through the rice from below. Alternative: a bamboo steamer lined with damp muslin, over a wok with boiling water. 1. Drain the soaked rice completely. 2. Spread in the steaming basket or muslin-lined steamer in an even layer. 3. Steam over vigorous boiling water for 20 minutes. 4. At 20 minutes: remove the steamer from the heat (or invert the basket over the pot), turn the rice mass over so the top becomes the bottom, and return to steaming. 5. Steam for a further 10–15 minutes. 6. The rice is done when: a pinch rolled between the fingers is fully sticky (no remaining chalky centre), stretchy, and cohesive. Decisive moment: The turning at 20 minutes — inverting the rice mass so the part that was exposed to the initial steam at the top is now closest to the heat source, and the part that has been at the bottom (closest to the steam) is now at the top. This ensures even cooking throughout — the top layer, which receives the most heat from below throughout the first 20 minutes, is furthest from the heat source for the second phase. Sensory tests: **Feel — the pinch test:** At 30 minutes total: pinch a small amount of rice from both the top and the deepest part of the steamer. Roll between the fingers. Correct: fully sticky, stretchy, slightly translucent throughout, no powdery or chalky resistance in the centre. Under-cooked: a chalky, dry, slightly resistant centre in the grain. **Texture at service:** Correctly steamed glutinous rice can be pressed into a ball between the palms and the ball holds its shape. It feels slightly warm, dense, and cohesive. It should not be wet or excessively moist on the surface — it is sticky from its starch structure, not from surface moisture.
- Leftover steamed glutinous rice, reheated by steaming for 5 minutes (not microwave — microwaving produces an uneven, tough result), is indistinguishable from freshly steamed - Glutinous rice served with mango and sweetened coconut milk (khao niew mamuang — the most famous Thai dessert) uses the same technique but the rice is mixed while warm with sweetened, salted coconut cream and allowed to rest before service — the coconut cream is absorbed into the warm rice
— **Gluey, collapsed mass:** The rice was cooked by absorption rather than steam, or excess water entered the steamer basket and the rice partially boiled. Steam must be dry — the water must not touch the rice. — **Chalky, under-cooked centre:** Insufficient soaking (less than 8 hours), or insufficient steaming time. The 8-hour soak is where the dish lives or dies for glutinous rice — a 2-hour soak will never produce the same result.
David Thompson, *Thai Food* (2002); *Thai Street Food* (2010)