Get your child used to foods, which will make life easier for you. Accustom him to whatever will be available on camping trips or foreign restaurants. Above all, try to get him used to eating cheese. Bread or biscuits with cheese, a tomato or apple, is a perfectly balanced meal, which takes 30 seconds to prepare another 30 seconds to clear up. It is easily portable, available in any roadside cafe in any western country and conventionally appropriate at any time of day. If you child will happily eat that combination you need never interrupt a days activities in order to think of a meal for him again. See Health and Safety Rules