Sous-vide is a method of cooking food slowly, at a precisely-controlled temperature. This article in the New York Times reports that this method is becoming more and more accessible to and widespread among home cooks. As I understand it, a typical home setup could be:
A large pot, full of water
An electronically-controlled immersion heater, immersed in the water, with its thermostat set to maintain a particular water temperature
Food, sealed in plastic bags or wrap, immersed in the water for a long time
As explained in the article, cook times could range from a short as an hour to as long as 72 hours, depending on the recipe.
Suppose one wants to use this method to have fresh-from-the-bath meat for Shabbat, setting everything up before Shabbat, and then removing and serving the meat on Shabbat.
Are there any Halachic issues that either would prohibit this scheme altogether or that need to be taken into account in implementing it?
I suspect that there could be issues related to:
leaving food under the care of an adjustable device, that you might want to fiddle with, and
causing the device to do more cooking as a result of removing the food from the water.
(Consult your own rabbi before implementing anything suggested here.)