Excellent suggestions here already. Look at your fave recipes at home and how to simplify them. Think fresh too. Fresh fruit always goes with us: oranges, apples, pears, etc.
Like planning your route, planning your menu ahead of time is key. Think of ways to prep ingredients ahead of time such as frying up ground beef and freezing or refrigerating. Chop onion, peppers and other items to put in a zipper bag for the fridge. That way you can measure and dump into the pot.
Remember, most RVs have microwave ovens. In addition to thawing prepped ingredients, you can also take along your favorite frozen pizzas and meals.