From the mid 1990s the thermo cooker, most commoly recognized as the thermo cooker was initially produced in Asia. It consisted of 2 pots, one within the other. The internal pot, built out of stainless steel, had been used to bring the food to the boil and the external, twin walled with a vacuum in between the walls, is used as the container to keep the cooking process continuing. To use the thermal cooker the food is placed into the inner pot and brought to the boil, simmered for about 10 minutes and then positioned in the outer pot for continued cooking. You will find a variety of thermal cookers on the market. Some use insulation material between the outer pot walls, others, use a vacuum.
