Abstract: A food service rethermalization process including a tray having first and second receiving hot dish receiving areas, at least one cold dish receiving area and an end wing area for holding eating utensils, napkins and the like. First and second selector or actuator knobs are mounted in the tray adjacent to the first and second hot dish receiving areas, respectively, and can be separately turned to on or off positions. When the tray is inserted in a rethermalization cart and the first and second heating pods of the cart are at the first and second areas respectively, the heating pods whose associated knobs are in the "on" position are switched on and the food at the associated areas thereby heated in a programmed manner. After the knobs have been turned as needed and before the tray is inserted in the cart, an over-all insulated cover is secured to and on top of the tray. The cover thermally separates and covers the different areas including the wing area.