Mac and cheese makes a great lunch to send to school! Here's how you keep it warm until lunchtime: -Warm the mac and cheese using one of the methods above until it is very hot -While the macaroni is heating up, fill a food Thermos with very hot water -When the macaroni and cheese is ready, pour the water out of the Thermos and dry it quickly -Put the mac and cheese into the warmed Thermos and put the lid on