The Thai iced coffee made with roasted rice and soybeans is called oliang.
Oliang is a popular Thai iced coffee traditionally brewed from Robusta coffee and a mixture of roasted grains and seeds. Depending on the recipe, that blend may include rice, soybeans, corn, sesame seeds, and cardamom. Brown sugar adds sweetness, while the roasted ingredients give the drink a smoky, toasted aroma.
The coffee is usually brewed strongly, strained through a cloth filter, and poured over ice. It may be served black or with evaporated milk, condensed milk, or fresh milk. That makes it different from cha yen, Thailand’s orange-colored iced tea, which is made from tea rather than coffee.
The name comes from Teochew Chinese: “o” means black and “liang” means cold or iced. The drink therefore has a name that describes its appearance and serving temperature. Recipes vary between vendors, so not every version contains both rice and soybeans, but oliang remains the canonical name for this Thai iced coffee style.