Rice is nice.
Several supermarkets are doing deals on microwave rice pouches. These are ideal for creating quick and easy supper dishes, not overly lightweight but for a couple of nights out they save cooking and drying meals or using up precious dried food stock.
Here's an example - Tijuana Tuna.
You'll need a Mexican rice pouch, a ziplock bag, a can of tuna (in oil), a red pepper and a can of beans (borlotti is my preferred legume.)
Dice the red pepper, open and drain the tuna and put both in the ziplock bag. Add the contents of the rice to the ziplock bag and seal. Gently massage the ziplock bag to mix and break up any chunks in the rice.
To eat - bring approx 3 tablespoons (45ml) of water to boil in a pan, add contents of ziplock bag and stir until heated through. Will serve two or one very hungry backpacker.