A device for chilling and heating of fluids, particularly beverages and liquid foods, is provided. The heating or cooling device can include a container encasing an insulation system, a cover or lid for covering the container, and the insulation system. The insulation system can include a coil made of a temperature-conductive material and fashioned to connect to an inlet in the cover and to an outlet in the container. The cover can also include a fluid reservoir for accepting the liquid to be processed, and an open section providing a passageway for adding additional insulating material to the insulating system while the device is in use. Once the device is assembled, a liquid can be poured into the fluid reservoir, pass through the coil that carries the liquid through the insulating system, and exit the container as a chilled or heated liquid.