basically, anything you can do in advance and reheat on the hob - chillie, curry, stew - with rice, pasta, potatoes. you could take garlic bread slices and toast them, mini naans, pitta bread. all the usual veg you would cook in a pan on the hob. to make life easy, you could take supermarket ready meals of the type you heat in a pan, or fry. cooked breakfast stuff (bacon, sausage, eggs, beans, toast, black pud, etc). lovely salads you can do too, with no cooking at all, or just potato salad, with steak.
the thought of no oven or microwave is a bit daunting at first i know, we're all so used to having them around, but it really isn't a problem, especially just for a few days. you could always get take-away too.
can you guess we have a caravan? i tend to freeze stuff that i make here at home and make double of, so that i always have at least the first couple of evening meals already made.
have a nice time, hope the weather is good (saturday should be the best, you could take a disposable bbq in a foil tray and use that if you're allowed by the site).