Roasting the tomatoes for a long time in a low-temperature oven concentrates the flavors. Try these roasted tomatoes as a topping for a pizza-style focaccia bread.
Preheat oven to 300 degrees and place the rack in the center of the oven.
Place tomatoes on a rimmed baking sheet in a single layer. Place shallots and thyme sprigs over tomatoes, drizzle with olive oil and sprinkle with salt. If doubling this recipe to use in Focaccia with Slow Roasted Tomatoes, distribute tomatoes, shallots, and thyme evenly between two baking sheets and place the sheets in upper and lower thirds of oven.
Roast until tomatoes are wilted and browning in places, 2 to 2 1/2 hours, turning tomatoes a few times.