Frothing is probably the most underappreciated part of coffeehouse culture. After all, without the foam, your cappuccino or latte is just plain espresso. It takes a little practice for even the best baristas to get the knack. Let us take a little dive into the art of frothing.

Most experts agree that it is best to begin with a stainless steel pitcher, some cold milk and an espresso machine with a steaming wand. Past that, there are as many differing ideas about the frothing process as there are blends of espresso.

The kind of milk you start with depends on the kind of foam you want to result. The more fat in the milk, the heavier and harder to froth it is. Skim milk is light and airy, whereas half and half is thicker and rich. Any container can be used, as long as it is not plastic or susceptible to melting or cracking with heat. Stainless steel is preferred because it is easy to handle.

Use the cup you plan to drink from to measure how much milk to steam. Keep in mind that the milk will approximately double in volume as it froths, so fill the cup with half the milk the drink calls for. A cappuccino is half steamed milk and half espresso, so to make a cappuccino you would fill the cup a fourth of the cup with cold milk. Pour the milk into the pitcher.

It is important that the tip of the steam wand is consistently held just below the surface of the milk. If it is too held too deep, the milk with scorch or boil before it froths. If it is not deep enough, it will blow the milk out of the pitcher and make a mess. Keep the palm of your free hand flush with the bottom of the pitcher. This will help you monitor the temperature of the milk without interrupting the process.

Slide the pitcher away from the machine, at a consistent speed, so that the wand remains the proper depth as the milk expands. At this point, the pitcher should be warmer than the palm of your hand. If it is not, plunge the wand deeper into the milk to warm it up. Be careful not to boil it. If the milk has gotten too hot, turn the steam off and tap the pitcher against the counter a few times to release any large air bubbles. Gently swirling it around a few times will help cool the milk off.

Using a long-handled spoon to carefully hold the froth back, add the milk to the drink. Be careful to pour in one continuous stream. A spoon may be used to add the desired amount of froth on top of the drink, but if the frothing is done well, the result is a fine micro foam that can be poured directly from the pitcher. Cinnamon, nutmeg or grated chocolate is a nice addition to any drink.