Tamping
Pressing the ground coffee in the portafilter into a level, compact puck before brewing espresso.
Tamping creates an even, firm bed so water meets consistent resistance. Level matters more than brute force — a tilted tamp encourages channeling.
A tamper that matches your basket diameter is important; a loose fit leaves untamped coffee around the edge.
Why it matters for small spaces
A correctly sized tamper and a level tamp are cheap, high-impact upgrades for anyone using a non-pressurised basket.