What is Vietnamese coffee, and why is it so different?

Vietnamese coffee is strong, dark-roasted coffee, usually made from robusta beans, that drips slowly through a small metal filter called a phin. It's often served with sweetened condensed milk, hot or over ice, and the result is bolder, thicker and sweeter than most coffee in the US.

Each part of that description, the bean, the roast, the filter and the milk, adds to what makes it so distinctive. Here's how they fit together.

Where did Vietnamese coffee come from?

Coffee arrived in Vietnam during the French colonial period in the 19th century, brought by French missionaries and planters. Over time it moved from plantations into everyday life, and Vietnamese drinkers made it their own. Today Vietnam is one of the world's biggest coffee producers, second only to Brazil, and coffee shops are part of daily life from big cities to small towns.

The bean: mostly robusta

Most coffee sold in American cafés is arabica. Vietnam grows mostly robusta, a different coffee species. Robusta has a reputation for:

• A heavier, more bitter taste with chocolatey, earthy or nutty notes
• Roughly twice the caffeine of arabica, bean for bean
• A thicker body that holds up well against milk and sugar

Robusta suits much of Vietnam's growing land, especially the Central Highlands, because the plant tolerates lower altitudes and heat better than arabica does. We go deeper on this in robusta vs arabica: why Vietnam grows robusta.

The roast: dark and sometimes buttery

Vietnamese coffee is usually roasted dark. Some traditional roasters add butter, sugar or other flavorings during roasting, which can give the grounds a slightly caramelized, oily sheen and a rich smell. Not every brand does this, so taste varies a lot from one bag to another. The dark roast is part of why the coffee tastes bold and slightly smoky.

The filter: the phin

The phin is a small metal drip filter that sits on top of a cup. You put grounds in the chamber, press them lightly with an insert, add hot water and wait while the coffee drips through a few drops at a time. A single cup usually takes around four to five minutes.

The phin makes a small, concentrated amount of coffee. It's closer in strength to a very strong pour-over than to espresso, but it's richer than ordinary drip coffee. It's also cheap, has no paper filter and needs no electricity, which helps explain why it became so common. If you want to try one, see how to make Vietnamese coffee at home with a phin filter.

The milk: sweetened condensed

The most famous Vietnamese coffee drinks use sweetened condensed milk rather than fresh milk or cream. A common explanation is practical: fresh milk was scarce and hard to keep in a hot climate, while canned condensed milk kept well. Whatever the history, the combination stuck. The thick, sugary milk softens robusta's bitterness and gives the drink a dessert-like texture.

The main drinks to know

• Cà phê đen: black coffee. Often served with sugar, hot (nóng) or iced (đá).
• Cà phê sữa: coffee with condensed milk. In Hanoi you'll often see it called cà phê nâu, "brown coffee".
• Cà phê sữa đá: coffee with condensed milk over ice, the drink most people mean by "Vietnamese iced coffee".
• Bạc xỉu: a Southern favorite with lots of milk and only a little coffee.
• Cà phê trứng: egg coffee, a Hanoi specialty with a whipped egg yolk topping.

Newer café drinks include coconut coffee, salt coffee and yogurt coffee, which each have their own posts in this series.

How does it taste compared with American coffee?

If you're used to a mug of medium-roast drip coffee, the first sip of Vietnamese coffee can be a surprise. Expect:

• Stronger flavor: more bitter and roasty, less bright or fruity
• Smaller serving: a phin yields only a few ounces of concentrated coffee
• More sweetness: if condensed milk is involved, it's sweet on purpose
• Thicker body: almost syrupy when mixed with condensed milk

A note on allergens and diet

Classic Vietnamese milk coffee contains dairy from the condensed milk. Some roasts contain butter. If you avoid dairy, look for a plain roast and use black coffee or a coconut-based condensed milk instead. Egg coffee contains raw or lightly cooked egg yolk.

How to try it

The easiest place to start is a Vietnamese restaurant or café; order a cà phê sữa đá. If you want to make it at home, you need just three things: a phin filter, a dark-roast coffee (Vietnamese brands are easy to find in Asian grocery stores and online) and a can of sweetened condensed milk.

Start with less condensed milk than you think you need; you can always stir in more.