I do summer meals on the cheap, using pretty much the same ingreidnets I'd use for winter meals.
Salads are good, couscous salads great, easy to make and cheap too (just don't get expensive salad ingreidints, things like carrots, tomatoes, onions, lettuce)
Wraps
Instead of sausages and mash, do sausages with new potatoes and grated carrot salad
Instead of chilli, do bolognese and serve in wraps or tacos with shredded lettuce, tomatoes and sour cream
Instead of a thick blended soup, keep the soup chunky and the broth clear for a summey version.
I've been thinking recently, pasta isn't that cheap any more, I've decided bread is cheaper if I make my own with value flour, and you xan make all sorts of different breads with just plain flour, yeast and some imagination.
I make pitta breads, normal bread, foccaccia, pizza bases, garlic bread, dough balls, naan bread and serve that with our meal instead of pasta or other carbs.