Iowa City, Iowa — We’re visiting family in the Midwest, and today is another in a series of 90-plus-degree scorchers. Hot stew on a hot summer day? The idea sounds absurd, if not downright tortured. The usual loyal kitchen helpers are likely to scatter the moment you crank up the stove. No doubt you’ll be left chopping and stirring in solitude. No worries. Ratatouille is a simple dish, just right for one cook. Use vine-ripened tomatoes, tender-skinned squash and sweet peppers, plus plenty of garlic and onion. Sauté each vegetable in olive oil, one at a time, then stir them all together in a sturdy pot and simmer the mixture, so the flavors commingle in a magical way.
