Abstract: A food warmer is provided which includes a metal food tray having side and bottom walls and a mouth at the top opening upwardly. A hollow well or sump vessel is provided around the food tray. The sump vessel is formed from a highly filled thermosetting plastic resin to provide a rigid monolithic body comprising at least about 15% and preferably about 30% to 80% by weight of an inert mineral filler, e.g. calcium carbonate (CaCO.sub.3) and fiberglass, and about 20% to 50% by weight of a thermosetting plastic resin so that the thermal conductivity of the food tray is at least about 50 times greater than that of the sump vessel. The sump vessel has bottom and side walls that enclose the sides and bottom of the food tray and is adapted to hold liquid, specifically water, as a heat transfer medium. An electric heating element is supported from a wall of the sump vessel between the walls of the sump vessel and the food tray for heating the food when energized.