Complex carbohydrates such as grilled vegetables can make for a filling and healthy side dish. Try preparing a mix of grillable favorites, including summer squash, zucchini, peppers, onions and mushrooms, brushing them lightly with olive oil and seasoning them with pepper to taste. Slice up the veggies ahead of time for simplicity, and make clean-up a breeze by wrapping them up in foil before grilling. If you're headed to a picnic destination that does not have grilling capabilities on site, no worries: Just roast the veggies in the oven beforehand and wrap them up to go. They'll taste good cold, too.