Cook or buy whatever you want prior to your trip. Put it into a sealable bag/pouch, but don't seal the top yet. Secure the top with a paper clip (or some other type of clip) and put it into your freezer at home for overnight keeping the top of the pouch upright so the contents don't leak out . Next morning after it has frozen, take it out and then vacuum seal the pouch. When you wan't to eat it, pop the pouch into a pot of boiling water for 15 minutes. Empty the pouch onto your plate/bowl and enjoy. If you haven't discovered Techni-Ice for keeping things frozen, do a Google search.