Serve on crackers or use as a dip with vegetables or chips. Humus is even easier. All you have to do is add water to a package of Fantastic Foods Hummus or Pesto Hummus mix, stir, and eat. Try Fantastic Foods Nature's Burger or Falafel mixes. Add water, wait 15 minutes, shape into patties, and fry.
Some campers swear by pasta.
The only drawback is that you have to bring a fairly large pot and then wait while the whole pot of water heats. If you want to go the pasta route, try one of the more quick cooking pastas like angel hair or orzo. Rehydrate some TVP and add tomato paste, water, onions, maybe some dried mushrooms, and seasonings for a sauce. Fresh fruit, like apples and oranges, can add variety. They do not require refrigeration.