My friends and I rarely use dehydrated foods but know the trade-off is weight.  I second the Tasty Bites packages. Pasta with pesto is good. I've been buying rice pouches and doing various toppings- last year was a "sushi bowl": rice with cut up nori, hard boiled egg (pre-boiled), tuna from a pouch, grated carrot, cucumber and a little soy and rice wine vinegar.