Abstract: A thermoregulating container provides for the heating and cooling of food and drink. The container is insulated and includes a heat exchanger system that can maintain the temperature of the contents of the container. The device may include modular elements that can detachably attach to one or many containers to selectively heat or cool the contents of the container(s). A first embodiment container includes at least one passage through the walls thereof, for conducting a heat exchanging fluid (water, refrigerant liquid, etc.) therethrough. The container passage(s) communicate with an attached reservoir module when such a module is attached to the container. When the module is attached, a heat exchanging fluid is circulated through the passage(s) in the container walls to heat or cool the substance therein accordingly.