The truth is, all you really need to cook utilizing the sous-vide method is the ability to put some plastic-wrapped product into a temperature controlled container of water. While not the first to do it, Martin Lersch made a sous vide rib-eye just by using a big pot of water, a thermometer and a plastic bag.
This is not your only option. If you don't like the idea of having a constant heat source going (e.g. the burner or you can also take the pot and try and put it in the oven), you can also use J. Kenji Lopez-Alt's beer cooler sous vide technique. The nice thing about this is that you don't have to watch it during the cooking process the way you do with the oven/burner methods. Fill up the container with hot water and put in your product. The other nice thing about this approach is the amount of space you have in the cooler.
Let's compare using my handy dandy chart that is guaranteed only to exist and not be accurate in any way:
Finally, my best advice for manual sous vide cookery is to:
- Bring food up to temperature prior to dropping it in the water. The colder your food is when it goes into the water bath the bigger the temperature hit will be (A frozen chicken breast is a giant ice cube).
- Monitor food and water temperature while cooking.
- Make sure that when your product comes out of the water bath, you immediate verify its temperature with an accurate thermometer. There is a line between incredibly moist and food poisoning, know which side of it you are on.
- Sear food when it comes out of the bag.