Preferably can be prepped in advance and transported to be cooked over a wood fire.
No contest: freshly caught trout.
It depends on what type of camping you will be doing. If you will have a cooler and ice with, you can marinate chicken and then cook it over the fire. Brats, hotdogs and burgers are easy to make over a fire. You can make foil packets of veggies to cook. If you bring a cast iron pan or pot, you can cook or reheat pretty much whatever you want. Pancakes and omelets are good for breakfast.
It gets more difficult if you are backpacking in. If that is the case, I recommend dehydrated meals - either a ready made packet or mix your own with dehydrated veggies, meat and broth powder.
Camping like drive a car to a campsite? Or backpacking for miles and setting up a tent? Very different scenarios.
For car camping with cooler available we always did tacos. Prep ahead and bring main filling, already cooked will make life easier (taco meat, chicken strips, lentils and walnuts, whatever), then reheat in a pot on the fire. Wrap tortillas well in foil and heat on edge of fire. Canned vegetarian refried beans (rosarita brand) are easy to heat on the fire edge too with the top off. Bring an avocado, salsa, and some limes.
Another easy one was any pasta dish, we would add chickpeas, chopped olives, olive oil, parm, and soft salad greens that would wilt.
My second favorite (after cv's freshly caught trout) is a foil packet, one of the ideas mentioned by ktr.
But the foil packet I learned and love has a ground beef patty in the center, sandwiched by sliced root vegetables (potato and carrot, or your choice).
You could also make it with thin steaks or lamb chops or other single-portion meats.
To make it last longer safely uncooked (while you go to camping site): prepare, freeze, transport, cook.
Thanks everyone! We will be doing lightweight camping with a cooler and ice, with the availability of a wood fire pit. We are doing this with our 5 month old so everyone wish us luck!