Something like this http://www.redflarekits.com/pc/3020/w/1200Kcal+Survival+Food+Ration+by+Mayday claims to store well in heat. Bad news is that it is thirst provoking so you are going to need water too.

MREs suffer shortened shelf life in heat.

Freeze dried will do ok, but there again, you need water and some way to boil it.