Eric, welcome! What about using some of those heating trays that they
have at cafeterias, with the sterno can underneath, to keep the slop
warm? Maybe you could rig up your own with a couple of bricks, a
baking tray, and a large can of sterno fuel? “Sterno” is a solid
flammable fuel often used for camping stoves and such, it is available
at most camping stores, or even hardware stores.