Most of the brewing recipes I have read for the Chemex recommend brewing enough coffee for two cups. The Chemex is suited for brewing multiple cups, so I understand why so many recipes outline how to brew two or more cups. But I like to drink one cup of coffee at a time. If I want another cup, I'll brew one later on. The only time I brew multiple cups of coffee is if I am making a brew for a member of my household.
While the Chemex is designed to brew multiple cups, I did not let this hold me back from buying the device. I was confident I could brew a good cup of coffee with the Chemex without having to brew any more than I needed. I wanted to know what the cup profile of the Chemex was without having to brew too much coffee at any one time. That would be a waste of good coffee.
I resorted to my standard V60 continuous pour recipe, which I outline below:
Pour 50 grams of water over the grounds.
Stir in the north, east, south, west directions and in every direction between.
Pour continuously until I reach 250 grams.
Swirl the brew to remove grounds from the top of the filter paper.
Wait until the coffee draws down.
I used this recipe because a lot of online recipes are written for "pour-over" rather than for a specific pour-over device. I understand why this is the case because a lot of pour-over devices have very similar mechanics. The V60 and the Chemex are both cone-shaped, which means similar—or the same—recipes can work on both devices. There are some subtitles between each pour-over device, but overall I find the V60 recipe I have written works well on the Chemex.
The key is dose. I brew with 15 grams of coffee to 250 grams of water. The coffee bed can look somewhat shallow but this is because of the proportions of the filter paper and the Chemex to the dose. Perception is everything. I decided to go ahead on my first brew and use this dose and see what would happen. The result was a sweet, flavoursome cup, rivalling some of the best V60 brews I have made so far.
In my experience with the Chemex, I find the sweetness of a coffee comes out more than it does in other brew methods. I find the coffee is clearer and I have so far never had any cloudiness or sediment in my brew. A clear brew is characteristic of pour-over devices, unlike the Aeropress or French press which are known to produce muddier—or cloudier—brews. I like the sweetness I can taste in the Chemex.
I use a coarser grind for my Chemex than I do for my V60. I do this because the Baratza Encore grinder I have recommends using the 20 setting, five points higher than the one I use for my V60. I thought this grind would be a good starting point—as all of the recommendations have turned out to be—and I was impressed. I tried to grind a bit finer but I was not as happy with the final brew so I went back to the 20 setting.
Would I recommend brewing one cup of coffee in the Chemex? Absolutely. Chemex filter papers are a bit more expensive than other filters like the V60, Kalita, or Aeropress filters. With that said, the cup profile of the Chemex speaks for itself.
I am still experimenting with my recipe for the Chemex. I have made a few cups with a little bit of bitterness that I think I could remove, perhaps with a slightly coarser grind. I tried brewing two cups at once and my cup was a bit more bitter than usual so I may coarsen my grind even more for bigger cups. But on the whole I feel confident in using the Chemex. The aesthetics of the device are eye-catching and I find myself often holding the Chemex in mid-air to take a look at the red-coloured liquid inside the device.
In short, you can brew one cup of coffee with the Chemex, even if most recipes tell you how to brew two or more cups at once.