ESPRESSO METHOD: Espresso machines force hot water through very finely ground and compacted coffee into the cups below. Good espresso is expensive to make because in order to extract the greatest amount of flavour from the coffee, a high level of pressure is required and thus a high specification machine. Yet when making espresso, it is important not to over-extract the coffee, which means the machine should be switched off sooner, rather than later. While the coffee is still coming out as a golden brown liquid, it is perfect. This liquid is the crema, that lies on top of the black coffee underneath. The crema will dissipate a few minutes after the coffee is made, but in those few minutes it will tell you everything about the quality of the espresso. Too light, or too thick or too thin: all mean that the espresso is sub standard.