Back in the 19th century, coffee was big business in Europe. As inventors sought to improve the brew and shorten the brewing time, espresso was born.
For many coffee drinkers, espresso is coffee. It is the purest distillation of the coffee bean, the literal essence of a bean. Espresso is neither a bean nor a blend. It is a method of preparation. Specifically, it is a method of preparation in which hot water is forced over coffee grounds at high pressure to produce a very concentrated coffee beverage with a deep, "strong" flavor.
There is no standardized one for an Espresso shot, but this is our standard recipe for a great espresso:
Dose: 19g +/- 0.5g Basket size:
Brew ratio: 1: 2 - 1: 2.8
Brewing time: 27-32 sec. (depending on dose and character of the bean)
STEP BY STEP:
1. Take the portafilter out of the group head of the espresso machine. Place it on a scale and tare the weight.
2. Rinse the group head thoroughly with hot water.
3. For a double shot, grind 19g of coffee into the portafilter. Place it back on the scale, put excess powder in a glass, or grind some more. The right grind is critical for a balanced, delicious espresso. You may need to adjust the fineness a bit. In general, the grind should be fine.
4. Distribute the coffee by dragging a finger over it. The most effective way is to alternate sides in 90-degree increments (top to bottom, then left to right, etc.).
5. Place the portafilter on a clean, flat surface and position the tamper horizontally on the coffee grounds. Apply downward pressure without pressing your palm into the bottom of the tamper (which can cause wrist problems in the long run). You don't have to tamp incredibly hard - just enough to evenly trap the coffee. Rotate the tamper slightly. This will smooth or "polish" the coffee grounds for even extraction.
6. Place the portafilter in the group head and place a preheated cup or two underneath. Start the water for the double espresso.
7. The extraction should start with a slow drip and then develop into a smooth, steady stream. Near the 30-second mark, the extraction ends. The shot will thicken and begin to "blonde" or turn yellow (the crema, small bubbles, will collect on the surface). Stop the shot as soon as this process begins.