Last summer, we made lentil salad once a week, (always making enough for at LEAST lunch and a snack, sometimes a second dinner).
cook green lentils until tender, cool (you can cook them a day in advance and put in the fridge, or you can cool in some ice). chop up feta, or cheddar, bell peppers, tomatos, carrots, celery, sometimes cucumbers, various summer veggies, and raisins. toss it all together with a vinegar-y salty vinegrette (I like half acv, half evoo, lots of salt, and some molasses). yumm. we love it.
also great is gaspacho with or without some good bread.
pita, hummus, feta, tzaziki, and olives or pickles.
Not really a one pot meal, but pretty easy and summery deliciousness: chicken fry bread salads.
make bread dough, stretch it flat, and fry it in a cast iron skillet.
meanwhile, shred some cooked chicken, put it in a little pot with a few garlic cloves, cumin, salt and peppercorns, and chicken stock to cover and some onions that were sauted in that pot first. simmer until the stock is pretty much all gone into the chicken (really no liquid left). (I know, it's cooking and on the hottest days you don't want to, but it's not that much heat added, and this dish is so good it's worth it to me. and you don't have to hover at all. It takes like an hour or more, so you can go and come back just checking it a couple times).
make guacamole by mixing an avocado with lime juice and salt.
spread on the breads guacamole, and top with fresh corn, fresh tomatoes, sourkraut and chicken. and optional salsa or hot sauce. love that one too.