What is a Dirty Matcha? (And How to Make One at Home)

A dirty matcha is a matcha latte with a shot of coffee poured through it. That's it. The coffee sits dark against the green, which is where the name comes from, and you get both drinks at once.

It's on cafe menus all over Auckland now. It's also one of the easiest things to make badly.

What it actually tastes like

Matcha on its own is grassy, savoury and slightly sweet, with a thick texture from the suspended powder. It's gentle. Some people find it too gentle.

Add coffee and the whole thing changes. The roasted bitterness cuts through the grass, the body gets heavier, and you end up with something closer to a dessert than a tea. Done well it tastes like a green-tea mocha. Done badly the coffee flattens the matcha completely and you've wasted good powder.

The ratio is the whole game

Most people pour too much coffee. A dirty matcha should still taste like matcha, with the coffee underneath it.

Start with roughly one part coffee to four parts matcha latte. A single concentrated shot through a full glass. If you can't taste the matcha any more, you've overdone it and you've essentially made a slightly odd latte.

Why the coffee matters more than people think

Here's the bit most recipes skip. You're pouring a small amount of coffee into a thick, creamy, slightly sweet drink. A light filter coffee disappears in there. So does a mild Arabica espresso once there's milk and matcha around it.

You need something concentrated and bold enough to hold its shape. That's the same reason Vietnamese Robusta works so well in ca phe sua da, where it has to punch through condensed milk and ice. Dirty matcha is the same problem wearing a different colour.

Phin-brewed Robusta is ideal here. It's thick, chocolatey and strong, and the chocolate note sits against matcha's grassiness rather than fighting it.

How to make one without an espresso machine

You don't need a machine. A phin filter makes a concentrate that works better than most home espresso anyway.

You'll need:

• 1 to 2 teaspoons of matcha powder
• 60ml hot water, around 80 degrees, for the matcha
• 150ml milk of your choice
• 20g Buffalo Robusta, phin grind
• Ice, if you're going cold

Method:

1. Set your phin brewing first. It takes 4 to 5 minutes and you want the coffee cooled slightly before it goes in.
2. Sift the matcha into a bowl or cup. Sifting matters, lumps don't dissolve later.
3. Add the 80 degree water and whisk hard until smooth and frothy. Boiling water scorches matcha and turns it bitter.
4. Fill a glass with ice, pour in the milk, then the matcha.
5. Pour the phin coffee slowly over the top so it layers.
6. Photograph it if you must, then stir before drinking.

Two things that go wrong

Boiling water on the matcha. Matcha is a leaf powder, not a bean. Water over about 85 degrees makes it harsh and astringent, and no amount of sugar fixes it afterwards.

Weak coffee. If your dirty matcha tastes muddy rather than layered, the coffee was too dilute. Concentrate it. A phin at a 1:5 ratio gets you there without any gear.

The caffeine question

Matcha sits around 30 to 70mg of caffeine per serve depending on grade and dose. Phin-brewed Robusta adds roughly another 180mg, as we broke down in our guide to caffeine in Vietnamese coffee.

So a dirty matcha made with Robusta is not a gentle drink. That's either the appeal or the warning, depending on your morning.

If you want to try it, Buffalo and a phin is all you need on the coffee side, and the Phin'omenal Pair bundles both.