The pressure cooker works by trapping steam inside the sealed pot, forcing the pressure to build to 15 pounds above normal sealevel pressure, and raising the temperature at which later boils from 212 degrees F. to 250 degrees F. Cooked at this higherthannormal boiling point, the fiber in food breaks down and the flavors mingle in onethird or less the standard cooking time. When cooking at high altitudes, increase cooking time by 10 percent for every 2,000 feet above sea level.For the pressure cooker to work properly, there must be sufficient room inside the pot for the steam pressure to build. Therefore, cookers are filled anywhere from halfway to threequarters of total capacity, depending upon the type of ingredients and the particular design.After the ingredients are assembled in the cooker, nest the lid into the pot, using arrows or other visual clues that are provided by the manufacturer, then turn the lid until the lid and pot handles line up. Some cookers have an additional locking mechanism that involves pushing a small lever into place. Most cookers are designed so that if the lid is not properly locked in place, the pressure wont rise. And remember, theres no peeking once the lid is locked in place and the pressure is up, it will be necessary to bring the pressure down to assess doneness or add more ingredients.High pressure is achieved as rapidly as possible by setting the cooker over maximum heat. Depending upon the quantity and type of food you are cooking and the size of the cooker, it can take from 30 seconds to 20 minutes for the cooker to reach high pressure. This process can be speeded up by adding a boiling rather than cold or room temperature liquid.When the meal is cooked, bring down the pressure by placing the cooker under cold running water. Its best to tilt the cooker about 45 degrees and run the water down one side of the cover, directing it away from the vicinity of the pressure regulator. The newer models of cookers also offer a quickrelease method that can be performed without moving the pot from the stove. Sometimes the pressure is allowed to drop naturally by removing the cooker from the heat and letting it sit for 3 to 20 minutes, depending upon the quantity and type of food in the pot. Some foods, paiticularly beeL require a natural pressure release to remain tender.The high heat of the pressure cooker mutes the flavor of garlic, herbs, and some spices. Recipes often call for whole spices, which will survive more successfully than ground, or for larger than usual quantities. Garlic, herbs, and spices may also be added at the end for a final few minutes of simmering after the pressure is released.A garlic press is indispensable when adding garlic at the end of cooking.

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