By Noah Kaufman
Updated January 08, 2015

All this week, people have been buzzing about the flat white's debut on the permanent menu at Starbucks. Even though this espresso-and-milk drink has been a staple in Australia for a very long time, it’s still relatively unknown to most coffee drinkers in the United States. So we went to Starbucks to see what makes a flat white a flat white.

At its most basic, a flat white straddles the line between a foamy cappuccino and a milky latte. But there are a few key differences. Starbucks coffee master Aubrey Hensley taught us how to make each.

Unlike a latte or a cappuccino, Starbucks's take on the flat white is made with two shots of ristretto espresso—a concentrated type of shot made with half the usual amount of water. The biggest difference, though, is in the milk. Before being steamed at the usual 185 degrees, whole milk (not wimpy 2 percent) is aerated for just three seconds to loosen up its proteins. The shorter-than-usual aeration time results in what coffee nerds call microfoam, and the milk becomes noticeably thicker than what's used in a latte and more velvety than the stiff stuff at the top of a cappuccino. Baristas swirl the steamed milk to give it a uniform texture, then pour it into the espresso. The result is both smoother and more potent than what you might be used to from Starbucks. Now, try not to get hypnotized by that perfect pour.