How do I dial in espresso for a new bag of beans?

Dialing in is the process of finding the 'sweet spot' for a specific coffee. Every bag of beans is different—different origin, different roast level, and different age—all of which affect how the coffee extracts. To start, pick a standard recipe. A 1:2 ratio is the industry standard: if you use 18 grams of dry coffee, aim for 36 grams of liquid espresso in the cup. Aim for a brew time between 25 and 30 seconds.

Once you pull your first shot, taste it. This is the most important step. If the shot is sour, salty, or thin, it is under-extracted. This means the water didn't pull enough flavor out of the grounds. To fix this, you need to increase the extraction. You can do this by grinding finer (which increases surface area) or by increasing your yield (letting the machine run longer to pull more water through the puck).

If the shot is bitter, dry, or astringent, it is over-extracted. The water pulled out too many of the harsh, woody compounds. To fix this, you need to decrease the extraction. Grind coarser or decrease your yield. The key is to change only one variable at a time. If you change both the grind size and the yield simultaneously, you won't know which adjustment actually improved the flavor.

In practice, keep a simple log of your adjustments. Note the coffee, the dose, the yield, the time, and the taste. This helps you learn how your specific grinder and machine respond to changes. Remember that freshness matters; as coffee ages, it degasses and becomes more soluble, meaning you will likely need to adjust your grind finer as the bag gets older. Dialing in is a skill that improves with practice, so don't be afraid to waste a few shots to get it right.