One thing I strongly suggest for your camper is a crock pot. AND Crock pot liners.
I always meal prep too. I know I have an oven, and range in the camper, but for some reason it makes me feel better having a meal plan, and having what I need to stick to that meal plan. So I get as much of the "work" done before leaving home.
Last weekend we went camping at Lake Bronson State Park in NW MN. We left Thursday night after work, and stayed till Monday (around 2:30 - 3PM). My husband and I are very outdoorsy and active people, and I knew we would be spending a majority of the day either hiking around the park with our dogs, or fishing from our kayaks. The main meal that I plan for the day is always dinner. I'm less concerned about lunches as we always have either hot dogs, sandwich options, or some form of leftovers or munchies.
Friday we had BBQ's. I had cooked them at home, placed the finished product in a Ziploc bag, and then froze it in our chest freezer. That way, when you are packing your camper's fridge for the trip your frozen food keeps the other fridge items cold while it thaws. (our camper is normally kept in our pole barn and has no electricity to try cool the campers fridge beforehand) By Friday morning (around 9AM) it was mostly thawed, so I place it in my crockpot, put it on low, and let it simmer all day. We stopped back at the camper for lunch around 1:30, so we stirred it, and then went on with our day. By the time we got back to the camper around 7:30ish, all we had to do was slice our buns, place our cheese, and scoop up some BBQ's.
Same concept for Saturday. Saturday was chili. Chili was made and frozen at home, left to thaw and chill in the camper fridge during the trip. Same time frame, wake up, put chili in the crock pot, come back for lunch, stir it. Go about your day, and when you get back after a full day of hiking or kayak fishing and are cold, wet and tired; just grab a good old paper bowl and fill it up with some nice warm chili.
Sunday was beef tips. The stew meat was frozen beforehand, but my gravy items are either canned or a dry package of soup. Mix everything in the crock pot in the AM. Bake a few potatoes over the camp fire when you get back, and dinner is served.
I use my crockpot soo much when camping. Its the best "Hands-OFF" method of cooking. And soo many meals can be cooked in a crock pot, so you don't really have to worry about getting tired of the same old meal.