The exact definition of a flat white varies, but it has a number of characteristics that are generally agreed upon. Here’s my take on a flat white:
- A double espresso (15 grams of beans to 30 grams espresso).
- About 100 grams to 120 grams of milk.
The milk should be steamed to produce a finely textured microfoam which is glossy, velvety, and slightly sweet. Milk for a flat white must not be frothy. It is not a Cappuccino. The sweetness comes from heating the milk, but not too much. I gauge the temperature simply by holding my hand against the side of the metal steaming jug. It’s about right just before it becomes uncomfortable to touch. It should absolutely not be scalding hot. The resulting drink should be easy and pleasurable to drink, without fear of burning the skin off the roof of your mouth.
Steam the milk
When steaming milk for a flat white, try to incorporate the air as soon as possible. This will give you more time to work it into the milk, before it gets too hot. Keep the steam wand tip close to the surface of the milk, no more than 2 to 3 mm below the surface. You want to hear the occasional “phfft” as small quantities of air are dragged into the milk as it swirls around in your jug. If you hear that awful roaring sound, present in so many “professional” coffee shops, you’re doing it wrong.
Pour the milk
The milk should then be poured swiftly through the crema of your freshly poured espresso. Try not to mix the crema in with the milk. Part of the pleasure of a flat white is the contrast in flavours between the more bitter dark brown top layer, and the slightly sweeter drink hiding below it.
Finally, whilst savouring your flat white is strongly advised, don’t savour it to the point where the microfoam has broken down into nothing more than warm milky coffee with a foamy head.