Abstract: A heating unit for heating the contents of a container includes an electrical circuit having a pressure responsive switch that is normally open and a thermally responsive switch that is normally closed, the pressure switch is responsive to a predetermined weight of the container on a pivotally mounted heating element for activating the switch to the closed position for activating the heating circuit. The thermal switch is responsive to an overheating of the unit to interrupt the circuit. The heating unit is provided with a heating element having a conical center portion surrounded by an annular flat or planar surface, for receiving containers having only a predetermined shaped bottom for accommodating the particular shape of the heating element.