I don't know of any food that will last if stored in a vehicle. The HOT- Cool - HOT cool cycle destroys even non perishables.
I would keep a case of MREs handy under my desk at the office, and some in a "go back" or "day pack". and the pack travels with me from house to car, car to work or whatever. Or I'd even have a case handy at home, and then going on a trip, throw the case of MREs and a couple gallons of water in the truck.
Food is just one of those things that you can't store in a vehicle for a long period of time, unfortunately.