A cooking vessel includes an upper element that defines a cook surface and a lower shell that defines a heat surface for contact with a heat source during heating. The upper element and the lower shell are joined together such that the cook surface and the heat surface are retained in a fixed spatial relationship with each other and a gas-filled cavity is defined between the heat surface of the lower shell and the cook surface of the upper element. An optional temperature sensor may be placed in contact with the gas for cooking temperature readout. Heat is transferred from the heat surface to the cook surface through the gas contained in the gas-filled cavity. Improved heat distribution is accomplished by static and dynamic means of enhancing gas convection. This promotes efficient and even heat distribution at low weight.