It's a bit of an investment :-
A dreampot or thermopot.
http://www.dreampot.com.au/
It makes travelling easier especially with kids (I know because I have six).
When we travel long distances we will cook breaky and make a stew, pack up and drive all day. At the next camp stop, I set up while the missus serves out hot stew.
We also use our dreampot at home a lot instead of using a slow cooker. With the cost of electricity it just makes good sense to use thermal store energy to cook your meals.