Let's get one thing out of the way - I'm not a rabbi, and nothing I write here should be construed as the words of an expert. However, I am an observant Jew and I do my best to follow the Law as I understand it.
➡️ It is completely permissible to prepare hot coffee on Shabbat via the pour-over method. This means:
You use coffee that was ground before Shabbat
You simply pour the hot water on the coffee (no swirling the slurry, no spinning with a spoon)
Depending on your practice, use a tertiary (third) vessel. Meaning you pour water from the boiler into a kettle or some other vessel, and from there pour on the coffee in the filter. The coffee will drain into your cup or a pitcher if you're making more than 1 cup.
➡️ You can also prepare simple Turkish coffee.
By that I mean to use very finely ground coffee and simply pouring hot water on it (again, depending on your practice, you may need an intermediary vessel between the boiler and the cup). Wait a minute for the grounds to settle and enjoy.
➡️ Finally, you can make a coffee concentrate before Shabbat and add hot water to it. I recommend a strong cold brew concentrate, or some like to brew multiple shots of espresso and add hot water to make a sort of Americano.
I'll admit that I used to make coffee on Shabbat in ways that aren't according to Halacha, because I didn't understand it well enough. I thought, as long as no electricity was involved, what could be the problem? Also, as the resident "coffee guy", I was always interested in preparing large amounts for special occasions (think Simchat Torah and other Kiddushim). So I would unwittingly (and errantly) prepare cups of coffee for myself and others with a French Press and AeroPress.
I realized a few years ago that I needed some concrete answers, so I invited the Rav of my community for a coffee demonstration. I showed him all these methods, explained how they work and why they are designed in these ways, and I got my answer.
The main problem with these methods, from a Torah POV anyway, is the issue of borer (removing the undesirable from the desired). The act of moving the filter through the coffee (as in the case of the French Press) or forcing the coffee through the filter (AeroPress) is forbidden on Shabbat and Yom Tov.
What makes the pour-over method permissible is the fact that you're just adding water and gravity drags the coffee through the filter.
Question: What about setting a timer on my electric coffee pot? Is that okay?
So, the problem is you can't heat up the water on Shabbat - your coffee brewer isn't built to hold the water temperature near boiling until it gets the signal to begin brewing, so that's a no-go.
An interesting thought though is that Yemenite Jews do allow the use of water that was brought to a boil before Shabbat to be heated again (say in a water boiler that's set to maintain a certain temperature). So if you're a Yemenite Jew who enjoys a cup of filter coffee and can't be bothered to pour the water yourself, discuss it with your rabbi before trying this at home. 😃
Question: Can I grind coffee on Shabbat or Yom Tov if I have a manual grinder?
Grinding (tochen) is one of the 39 melachot, and so it's not allowed on Shabbat. But what about Yom Tov - if I can transfer fire for the purpose of cooking, so why not (manually) grind my coffee? Everyone knows it will taste better.
So, turns out this is discouraged. And while you and I can taste the difference, I think the nuance (taste-benefit analysis) would be lost on most poskim. Still, I encourage you to contact your local posek. If you do grind on Yom Tov, you should do so in a manner other than you normally would, such as switching hands (shinui).
What about you?
Do you have any comments, critiques or suggestions? I'd like to hear them.
Shabbat Shalom, David