What you’ll need: Espresso Machine, Portafilter, Tamper, Dry Cloth, Cup, Digital Scale, Timer
Preparation
⇒ Make sure your machine has been turned on for at least 10 minutes and purge a few seconds worth of water through your grouphead
↳ This makes sure that all components are hot and ready to extract a great cup of coffee
↳ You can also use the water purge to eat up your portafilter
⇒ Using a dry cloth, wipe down the portafilter and the basket
↳ If this is your second shot, make sure to remove any coffee residue and oils from the portafilter
⇒ Weigh and grind 18g of coffee
↳ The grind for espresso is very fine, but it is still granular. If your grind has the consistency of powdered sugar is it likely too fine.
⇒ Place the ground coffee into the portafilter
⇒ Level the ground coffee in your portafilter
↳ Tap the basket with the heel of your hand to settle the grind and distribute the coffee evenly with your finger. Swipe back and forth.
↳ An unleveled or lumpy coffee bed will have an uneven density once tamped, which causes water to run through the coffee more quickly in some sections than others.
⇒ Place the portafilter on a flat surface and place the tamper level on top of the grounds
↳ Apply pressure downwards, not too hard, but enough to seal the coffee in evenly
⇒ Purge another few seconds worth of water through the grouphead
↳ Again, this is to ensure that all components of the espresso machine are warm enough
Extraction
⇒ Position the portafilter in the grouphead
↳ Insert it gently so that you don't create cracks in your espresso puck
⇒ Place a cup on a digital scale and place them both underneath the portafilter
↳ Make sure to tare the scale at this point
⇒ Start the brewing process and start a timer at the same time
↳ Depending on the machine you have, the extraction should take anywhere from 23 to 28 seconds
↳ If it takes too long this means your grind is too fine; if it's too fast it means your grind is too coarse
⇒ The shot should start with a slow drip, and develop into a gentle, even stream
⇒ Your espresso is now ready to serve!
Cleaning
⇒ Remove the portafilter from the grouphead and knock out the puck
⇒ Wipe the basket clean
⇒ Purge the grouphead with hot water for 3 seconds
⇒ You're now ready to start brewing espresso again
Source: idrinkcoffee.com