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Sous vide, which is French for "under vacuum," is a method of cooking, in which food is placed in tightly sealed bags and cooked in water at a low, controlled temperature. This means no more worrying about overcooked steak or chicken.

Equipment
Sous vide was first used in the early 1970s in France. Thanks to a steady increase in popularity, sous vide has been making its way from gourmet restaurants to home kitchens. You need three tools to sous vide: a way to vacuum-seal the food, something in which you can submerge the now vacuum-sealed food, and a way to maintain and monitor the temperature of the water bath.

Equipment specially designed for sous vide cooking can be expensive, but you don't need a fancy thermal immersion circulator to make a great sous vide-cooked dish. Cookingsousvide.com has an amusing yet useful flow chart to help you determine which sous vide machine you should use.

You can find a basic counter-top vacuum sealer for about $50, but higher-end models can be on the pricier side. If you are a first-time sous vider and aren't ready to make the investment, you can try using a handheld vacuum sealer. Make sure the bags you are using are safe for sous vide cooking.

As far as the water bath goes, Popular Science suggests using a rice cooker that you can turn on and off; the ones that automatically sense when to turn off won't produce the desired result. Slow cookers are also said to work well. Sous vide can also be achieved using a large pot on the stove.

Temperature and time both affect the quality, texture and taste of sous vide dishes. You can plug your slow cooker into a sous vide cooking controller, which will keep the temperature constant.

You can also try using a meat or kitchen thermometer with a cord. Sous vide thermal circulators ensure that all of the water in the container is the same temperature. They also make for more precise temperature control. The goal should be to have the temperature fluctuate less than 1 degree Celsius.

Cooking
The first step is to add flavoring to the food as you would with other cooking techniques. You can rub the seasoning on whatever you are making, or you can put seasoning in the bag with the food.

If you plan on using your own vacuum sealer, freeze any liquid before you add it to prevent the vacuum from sucking up your marinade. Heat the water until it arrives at the proper temperature. The food is usually cooked at the temperature at which it will be served. Let the food cook for the required period of time, rotating every six to 10 hours, if applicable. Add the finishing touches to the dish. Perhaps you will have to saute your steak for a few minutes so an outside crust forms.

Safety concerns
Cooking at a lower heat raises concerns about bacteria and salmonella. Some kinds of bacteria thrive in oxygen-free environments, like those caused by the vacuum-sealing process. Make sure you vacuum-seal food while it is cold and cook it right away or store it in the refrigerator until you are ready to use it. Check out sous vide expert and author Douglas Baldwin's safety guide for more information.