3. Heat 1⁄4 cup olive oil in a large, shallow saucepan over medium-high heat. Add the leeks and saute for a few minutes. Using butcher twine, tie up the bay leaf with the thyme sprigs to form a kind of bouquet, and add to the pan. Add the reserved carrots, lima beans, and corn along with the tomatoes, and season generously with salt and pepper. Cook for about 2 minutes, or until just warmed through, remove the herbs, cover, and remove from the heat.