Snack Foods
You can bring nearly anything to snack on, provided it will keep for long enough to make it into your mouth. Old standbys such as trail mix and granola are excellent because they are dense, portable and chock full of energy. Tree nuts, dried fruit, beef jerky and other salted and preserved meats are also great for munching on the trail. Fresh fruits such as apples and oranges are durable enough for a camping trip, but berries go bad quickly and are easy to squash, so they should be left at home.
Breakfast Eats
Hard, crusty breads such as baguettes and bagels can last for several days with no refrigeration, making them great for breakfast meals. For longer camping trips, you may want to also bring along hot cereal such as oatmeal or grits. If you prefer cold cereal for breakfast, bring along some powdered milk to have with it. If you're feeling up to doing some serious cooking in the morning, you can make pancakes easily with a mix. Use vegetable oil instead of butter to grease the pan, because it will not go rancid. Tea, coffee and cocoa will help you warm up after a cold night in the wild.
Lunch and Dinner
Peanut butter and jelly makes for a good campsite lunch and will even do for dinner in a pinch. Canned soup is also good for both lunch and dinner. If you prefer soup to sandwiches, heat some extra soup at dinner and then leave it in a thermos to eat for lunch the next day. Some campers prefer ramen noodles to canned soup, because they are more portable and don't require a can opener. If you feel more ambitious about your cooking, makes a meal based on dry bulk foods, such as rice, lentils, pasta or beans. You can also throw in some potatoes, beats, carrots and onions, because root vegetables tend to take a while to go bad.
Some of your snacks can be used to spice up your cooking as well. Chunks of beef jerky and dried fruit go well with rice. Pickled vegetables are also a good choice, because they add flavor and don't go bad. Canned sauces, such as spaghetti sauce and chutney, can also be used to flavor your meals. Don't neglect to bring a few spices and seasonings with you. Even a bit of salt and some honey can do wonders for an otherwise bland dish.