Spice kits.Hands down, the easiest thing you can do is pack along a few spices. For a short hike, you can use mini-zipper-locking bags for storage, but on a long trip, you'll find that over time the zipper channels get blocked with a combination of dirt and spices. To avoid that problem, buy tiny plastic containers, available in outfitting stores. (Don't use film canisters, which are contaminated with chemicals.) 

Here's what to put in them:

• Salt and pepper
• Cayenne pepper sauce
• Soy sauce
• Garlic and oregano (can be mixed together)
• Onion flakes
• Dried mushrooms or sun-dried tomatoes (lots of flavor per ounce!)
• Boullion cubes

Home dehydrating.If you can cook it, you can dry it. Dehydrating meals brings home-cooked food right to your tent. Dehydrating works especially well with sauces, chili, thick soups, and fruits and vegetables. If you think you'll be doing a lot of dehydrating, spring for a multi-tray dehydrator. 

Warning: it takes a little bit of experimenting to get the quantities right.

Health food stores.Health food stores carry an interesting assortment of foods that work well in the backcountry, including quick-cooking grains (cous-cous and polenta are practically instant), unprocessed cereals (more nutritious), interesting instant soups, and just-add-water foods, including black beans, refried beans, and hummous.

Asian food stores.If you like noodle soups, but don't want to eat the same thing day after day, try the offerings at an Asian market, where soups come with a wide variety of noodles and species, including packets of dried onions and spicy oils. Also check out packaged miso soups.

Fresh Foods.Onions, potatoes, cabbage, carrots, and garlic can all survive a while without refrigeration. You can't take too many, because of the weight, but a little bit of fresh flavor goes a long way to add zest to soups and sauces.