Firstly, take a good look in your cupboards / freezer. Sometimes if we are really stretched, I can get a week from what we have here, just adding milk from the shops. The food might be a bit strange, but we try to have fun with it!
Second, bulk out meals with more of the cheap stuff, less of the costly stuff. For EE, that would indicate more potatoes / pasta / rice / lentils than meat / fish etc. If you normally get 3 portions of sauce out of 500g mince, add lots of veg (celery, mushrooms, carrots, onions) so that you get 6 portions - then, either eat the same meal twice, or vary it - eg spag bol first day, save half the sauce, add chilli and a can of kidney beans, you have chilli con carne the next day.
Find out what veg are cheap / on offer in your supermarket / market and use them as the basis for your meals - they will still be free on the plan, increasing your superfree foods and saving the pennies too
If you like spicy food, look at making dahl, serving it with rice and a maybe a veg curry or side dish. gotta be the cheapest, tastiest meal around.
Try to keep thinking about the superfree element of our meals - it is the easiest thing to forget about when budgeting. Yes, Jacket and beans is very cheap, but where will you get your superfree - will it have to be from an expensive bag of salad? Instead of the beans, you could make a coleslaw (cabbage and carrot etc etc, yog etc) for your jacket potato!