Thai Iced Coffee (Oliang): How to Make It, Black or With Milk

Thai iced coffee is strong, sweetened coffee poured over ice, drunk black as oliang or topped with evaporated or condensed milk. To make it, put about 20 g of oliang powder — or dark-roast coffee with a pinch of cardamom — in a cloth coffee sock, pour 200 ml of boiling water through, let it steep for ten minutes, sweeten it while hot, pour it over a tall glass of ice and float a couple of tablespoons of evaporated milk on top.

Its flavour is unlike most iced coffee: dark, toasty and slightly smoky, thanks to a traditional blend that is not only coffee.

The recipe

1. Put the coffee in a cloth sock — or a French press — over a heatproof jug.
2. Pour the boiling water through and let it steep for about ten minutes, until very strong.
3. Sweeten it while it is hot. Sugar barely dissolves once coffee is cold.
4. Pour it over a tall glass of ice.
5. Float the evaporated milk on top, and stir before drinking.

What oliang is

Oliang is both the drink and the coffee it is made from. The blend is robusta coffee mixed with brown sugar and roasted grains and seeds — cardamom, corn, soybeans, rice and sesame among them — and the high-roasted grains give it a distinctly smoky, toasty aroma alongside the coffee.

The name comes from the Teochew Chinese pronunciation of 烏涼, meaning "black and iced"; Teochew speakers make up the majority of Thailand's Chinese community, and the word describes exactly what the original drink was.

If you cannot find oliang powder, a dark roast with some robusta in it and a pinch of ground cardamom makes a good approximation. The arabica and robusta guide explains why robusta tastes heavier and more bitter — qualities that stand up well to sugar, milk and ice.

The cloth sock

Thai coffee is traditionally brewed in a tungdtom: a cotton cloth bag sewn onto a metal ring with a handle, the same tool used for Thai tea. The coffee goes into the sock, boiling water is poured through into a carafe, and the sock is left to steep for about ten minutes, until the brew is very strong.

The long steep is deliberate. The coffee is going to be poured over ice and loaded with milk and sugar, so it has to start as a concentrate.

Black or with milk

Thai coffee stalls offer several versions:

• Oliang — black coffee with ice, usually sweetened.
• Kopi — black coffee with condensed milk.
• Oliang yok lor — black coffee with ice and fresh milk.
• Kafae yen — coffee with condensed milk, ice and fresh milk.

Evaporated milk, served in a small jug for the drinker to add, is another common finish, along with a small jug of syrup for sweetening to taste.

Why it has to be strong and sweet

Ice melts as it chills the coffee — every gram absorbs about 334 joules — so a hot brew poured over a glass of ice ends up noticeably diluted. A ten-minute steep at a strong ratio leaves room for that.

Sweetness has a physical side too. Sugar dissolves readily in hot coffee and slowly in cold, which is why it goes in before the ice; and cold dulls the perception of sweetness, as the iced latte guide explains, which is one reason iced coffees are sweetened so generously.

The numbers add up quickly. The USDA lists sweetened condensed milk at about 54% sugar, so two tablespoons — about 38 g — bring roughly 21 g of sugar and 122 kcal. Two tablespoons of evaporated milk, about 31 g, add about 42 kcal and 3 g of milk sugar. A glass sweetened with condensed milk and topped with evaporated milk therefore carries around 165 kcal and 24 g of sugar, before any sugar in the oliang blend itself.

Coffee in Thailand

Thailand grows coffee, but it drinks more than it grows. The US Department of Agriculture estimates Thai production for 2026/27 at about 900,000 60-kg bags and domestic consumption at about 1.1 million, with the difference made up by imports.

For Thailand's neighbours' versions, see the Vietnamese coffee guide, and for Hong Kong's coffee-and-tea blend, the yuenyeung guide.