1.Grinding the beans
A standard 30 millilitre (1 fluid ounce) double espresso shot should pour through the machine in 26-30 seconds. Any less than that and the grind is probably too course, any more and it’s too fine.
Because coffee absorbs water, the setting of the grind needs to be adjusted regularly as the pour will vary according to the humidity in the air. The more humid the day, the coarser the grind needs to be to compensate.
2. Heating the milk
Burnt milk can ruin a perfectly good espresso and is a common mistake in making a latte. Gee recommends using a thermometer to take the milk off the heat as close to 65 degrees centigrade (150 degrees fahrenheit) as possible.
If using a steam wand on an espresso machine, the wand needs to start off about 1.25 centimetres below the surface of the milk and moved slowly upwards as the heat increases to bring about a swirling motion. It must remain below the surface, otherwise air pockets develop in the milk causing large tasteless bubbles.
At the end of the process, baristas often bang the jug to get rid of any bubbles and achieve a smooth, silky texture.
3. The pour
For a latte, pour the milk on top of the espresso, in the centre of the cup, as steadily as possible.
Use a small spoon or spatula to guide out more froth in the final 1-2 centimetres of the pour.