This is a question for your rov.
The Mishna Berura 253 discusses this concept, as well as the various stages of preparedness of cooked food that are allowed and are problematic.
Additionally, a coffeee-maker that audibly grinds the beans has a separate issue (also in the M.B. 253)
Here are some opinions on the issue, cut-and-pasted from other sites:
First Site (yeshiva.org.il)
Automatic Coffee Maker on Shabbat/Yom Tov
by Rabbi Jonathan Blass
Question:
May a person set a coffee pot on a timer before Shabbat to make coffee for Shabbat morning? If this presents a problem of Bishul, then can a person set a coffee pot on a timer to make coffee for a Yom Tov morning?
And, are either of the above two questions handled differently if the coffee maker is the type that both grinds the beans and makes the coffee automatically (as opposed to the “standard” machine which uses preground beans)?
Answer:
Second Site (eretzhemdah.org)
Question: May one set an automatic coffee maker on a timer so that it brews the coffee on Shabbat morning? (Obviously, the ingredients would be put in and the settings adjusted before Shabbat, and no electrical switches need to be pressed to remove the coffee.)
A final issue is that the Rama (OC 252:5, as opposed to the Shulchan Aruch, ad loc.) forbids operating from before Shabbat a mechanism that is forbidden to operate on Shabbat if it makes noise because it is degrading for Shabbat (avsha milta). It is permitted only if people often set up the mechanism in advance and thus there is no reason to suspect Shabbat desecration occurred (ibid., regarding a clock that chimes). Since coffee makers are usually not operated on a time delay, this could be a problem. However, most machines are probably not loud enough to cause a prohibition, which exists when it can be heard in another room (see Igrot Moshe, OC IV, 70).
There are (and will be) many models of coffee makers, so one must ensure that his meets all the requirements and not assume or quote us as giving a blanket leniency.
rabbiofberlin-
“As a matter of fact, ‘cholent” is cooked mainly during shabbos, as long as it is fulyl covered, etc.“
If I remember correctly, cholent has to be cooked to a certain degree before Shabbos. (I’m relying on my memory here, and don’t remember if ki’machal ben drusoi, mostly cooked, or some other shiur. If anyone can help with specifics it would be appreciated).
I didn’t know that instant coffee was pre-cooked, and was wondering why instant coffee must be added after the hot water if it’s already cooked since “ain bishul achar bishul”.
The star-k website addresses this: Note: Some opinions consider dry foods that dissolve when added to hot liquid a davar lach, a liquid. To allow for this opinion, it is better to put such additives only into a kli sheni after the hot liquid has been added. For example, it is best to first place hot water into a cup and then add instant coffee.