The Practical Guide to Dialing In Pourover Coffee

Here's all you really need to know:

Pick any recipe you want (we suggest ours, of course). Brew a cup. Taste it.

If the coffee is harsh/astringent/bitter/metallic, you need to decrease extraction.

If the coffee is sour/vinegary/vegetal/underwhelming, you need to increase extraction.

To increase extraction: grind finer, use more water, use hotter water, use more agitation, or increase brew time.

To decrease extraction: do the opposite, so grind coarser, use less water, use cooler water, use less agitation, or decrease brew time.

If you taste both under and over extracted type flavors, you have an extraction evenness problem, which could be from grinding too fine (see two paragraphs down) or from a poor quality grinder or from not pouring the water evenly or not using enough water for your bloom or not letting it bloom long enough.

The only way to know for sure that you’ve bloomed with enough water and for long enough is if you don’t taste under and over extracted type flavors in the cup. If you do taste both, make sure the grounds have more or less stopped bubbling before you start your main pour on your next brew. If you aren’t using at least 2.5x the amount of water as grounds (example, at least 50 grams of bloom water for 20 grams of ground coffee), increase the amount (3x or even 3.5x is fine). If you are doing these things, and still tasting both under and over extracted type flavors in the cup, the problem is likely not the bloom.

The longer you wait between pours, the more agitation the next pour will cause as there's less water to absorb the energy of the new falling water. Waiting longer between pours will also increase the brew time, so this will significantly increase extraction. The more pours you do, the higher the agitation will be for the same reason - there's less water in there, so the grounds themselves get churned up more.

And finally, the real kicker, at a certain point, grinding finer makes extraction go down rather than up due to channeling - the water cannot flow evenly through the grounds, and either 1) the channeling water extracts harsh tannins/tannin-like compounds from the grounds in/around the channels because it is flowing with higher energy, or, 2) the harsh tannins/tannin-like compounds always get extracted, but if the brew water flows through enough grounds (not through channels), the grounds themselves filter these compounds out. Avoiding this is key.

All pourover recipes just use some combination of these variables (grind size, water:coffee ratio, water temperature, amount of agitation, and brew time) to end up with a balanced brew. Every recipe will require you to brew a cup, taste it, decide what's wrong with it, and then adjust to make the next cup taste better.