With summer here, the time is perfect for gratins. Sure, everyone is firing up the grill, but let’s face it-grilled vegetables only hold their appeal for a while, and then you want something with a little more depth of character. All those vegetables that are great on the grill are also great in a gratin. Easy to make, gratins can be made in advance and will keep overnight, and are good hot from the oven, or at room temperature. What’s not to like?