We're a family with a dog and small kids, so if we're stuck away from home at lunchtime for some reason, it can be hard to find somewhere to eat or shop for food.

I'm assembling items for a long life emergency picnic. Food items should last for at least a year, preferably 2, and can be stored in a vehicle, so it'll be mainly stuff that's stored in sealed containers and packets.

I was wondering if any of you have tried army rations, and if any of those are any good, and if there's a good substitute for a sandwich, or maybe some way of constructing a sandwich from long life components. Is there a good picnic item that has a surprisingly long shelf life?

cold food would be easier, but hot food could be prepared in a heater pouch (Might be more of an option as the kids get older)