Hi, Just wondering what other parents do when ...

Hi, Just wondering what other parents do when they are out and about and baby is eating solids? When I go to places where there are no microwaves in the parents room, I can't heat up DS's food. I make his food and then freeze it, so I defrost a day before and leave it in the fridge. When I take it out with me, it's still quite cold and I'm not keen on feeding him cold food. What do other parents do? I could just take a jar of commercial baby food but ideally would like him to eat home cooked food. Any suggestions please??