Measure 18-20 grams of finely ground coffee beans (preferably dark roast) for a double shot of espresso.
Fill the espresso machine's water reservoir with fresh, filtered water.
Turn on the espresso machine and let it heat up for a few minutes.
Place the ground coffee into the portafilter and tamp it down firmly and evenly.
Attach the portafilter to the espresso machine and place an espresso cup under the spout.
Start the extraction process and let the espresso flow into the cup for about 25-30 seconds, or until you have 60 ml of espresso.
Serve the espresso immediately, either on its own or as a base for other coffee beverages.