My standbys in those circumstances are endless variations on the stir-fry theme - start off with cooking the protein, whether meat or fish, add the veg and meanwhile cook some noodles on the other hotplate.
Katherine Whitehorn's book 'Cooking in a Bedsitter' is still in print and there is even a Kindle edition now and hence the ideal cookbook for SC holidaymakers - great for campers as well! It was my culinary bible when a student. It's very helpfully organised around recipes if you only have one gas ring or hotplate, recipes for cooks who have the luxury of two and alternatives for filling the potato shaped space in your tum! It even has a section on 'entertaining' and even though I'm no longer cooking on a just a hotplate, I still more often than not follow the tip of only serving one hot course which is topped and tailed with a cold starter and dessert when I have a crowd round for a meal. When I think about it, many of her recipes are still staples of my culinary repertoire - its just that I now make the slow cooked one pot stews in the slow cooker rather than using an asbestos heat diffuser on a gas ring under a stoneware Dutch pot!
A variation of one of her recipes which is still a great one-pot standby is to cut chorizo into chunks, fry it off and put it to one side and cook chopped onions in the fat from the chorizo. When the onions are soft add a tin of chopped tomatoes, seasoning and herbs of choice, and then return the cooked chorizo to the pan along with a tin of drained cooked beans (not baked beans but something like ready to use butter beans or whatever is available) and leave to simmer for as long as you can resist the delicious smell. A great meal to have with just a really nice crusty loaf or some green salad or rice or noodles or pasta as the fancy takes you. Or a jacket potato if you have the luxury of a microwave. The basic quantity is a good serving for two with little else but if there are more of you just add more beans! Or buy a bigger loaf! Or add some stock and tell them it is soup!
SM