Slow-Roasted Summer Tomatoes

Slow-roasting, which caramelizes and intensifies the flavor tomatoes and gives them a meatier, more robust texture, is a perfect way to preserve these summer gems. Once you've roasted the tomatoes, they'll keep in the freezer for months.If you don’t have fresh thyme, you can use another fresh hardy herb like oregano or rosemary—or leave it out altogether.

• 3 Tbs. plus 1 cup extra-virgin olive oil
• 4-1/2 to 5 lb. medium-large ripe beefsteak tomatoes (about 12), stemmed but not cored
• Kosher salt
• Granulated sugar
• Scant 1 Tbs. balsamic vinegar
• 3 to 4 cloves garlic, very thinly sliced
• 2 Tbs. fresh thyme leaves

Tip:

Don’t use unrimmed baking sheets or the oil and juices will spill out; instead, use ­several shallow gratin dishes if you don't have rimmed baking sheets.

Heat the oven to 350°F. Line a 12x17-inch rimmed baking sheet or two 9x12-inch rimmed baking sheets with foil. If you have parchment, put a sheet on top of the foil. Coat the pan or pans with 3 Tbs. of the olive oil.

Cut the tomatoes in half through the equator (not through the stem). Arrange the halves, cut side up, on the baking sheet, turning to coat their bottoms with some of the oil. Sprinkle a pinch each of salt and sugar over each half, and drizzle each with a few drops of balsamic vinegar. Arrange the garlic over the halves and top with a generous sprinkling of thyme. Pour the remaining 1 cup olive oil over and around the tomato halves.

Roast in the center of the oven until the tomatoes are concentrated, dark reddish brown (with deep browning around the edges and in places on the pan) and quite collapsed (at least half their original height; they will collapse more as they cool), about 3 hours for very ripe, fleshy tomatoes, about 4 hours for tomatoes that are less ripe or that have a high ­water content. Let cool for at least 10 to 15 minutes and then serve warm or at room temperature. Be sure to reserve the tomato oil (keep refrigerated for up to a week) to use on its own or in a vinaigrette.

Quicker-cooking variation: Remove the seeds and gelatinous pulp (poke them out with your fingers) before roasting. These tomatoes cook more quickly (check for doneness after 2 hours) but yield a slightly flatter, less meaty—but perfectly pleasant—result.

Plum tomato variation: Substitute plum tomatoes, cut in half through the stem end and seeded. The roasting time will be about 2 hours. Roasted plum tomato halves hold together particularly well; layer them in a ­terrine or roll them up, stuffed with goat cheese and basil, as an appetizer.