Caponata, that richly delicious blend of eggplant, peppers, onions and tomatoes, has been my go-to summer vegetable stew for years.

Ratatouille is basically caponata with the addition of zucchini and quite a bit more olive oil, but until this year I’d never made it. Now, though, thanks to my friend Nancy and to Melissa Clark and her NYTimes “A Good Appetite” column, ratatouille is in serious competition with caponata for favorite summer vegetable stew.  The zucchini adds another surprisingly rich layer of flavor to the caponata blend, and as an additional bonus, zucchini’s place in ratatouille is a great way to use this always-abundant summer vegetable.

I had noticed Clark’s recipe for sheet-pan ratatouille in a recent column, and been intrigued by both her article title, Ratatouille, Simplified and Just as Satisfying and the opening line of her recipe description: “Cooking ratatouille on a sheet pan in the oven isn’t just easier than cooking it in a pot on the stove, it’s also better: richer and more deeply caramelized in flavor.” The “richer and more deeply caramelized” definitely spoke to me, but it was Nancy’s endorsement that spurred me to try it.  Not only is this ratatouille yummy, Nancy emailed, “The ratio of effort vs reward is heavy on the reward.”  Here, at the end of summer, with the last of the season’s harvest coming on, an easy recipe was very appealing.

Clark’s method combines quick vegetable preparation and simple sheet pan technique.  Slice the zucchini into ¼ inch rounds, the onion into thin slices, the eggplant into inch-chunks and the peppers into chunks or strips.  Combine the zucchini and onion on one sheet pan and the eggplant and red pepper on the other.  Add garlic, springs of rosemary and thyme, salt and ¼ cup of olive oil to each pan and toss.

Put both pans in a 425 oven and roast for 40 minutes, turning the vegetables two or three times with a spatula.  At first, the vegetables will give off liquid, then they will reabsorb it and begin to caramelize, all on the sheet pans, in the oven, out of sight.  The final time-saving step is simply scattering cherry tomatoes over the eggplant and pepper pan where they burst and melt into the caramelized eggplant and pepper, covering them in a quick and easy tomato sauce.   The additions of goat cheese and olives are delicious too, but even without them, this dish is a lovely celebration of the end of summer.

Sheet-Pan Ratatouille with Goat Cheese and Olives

1 large onion, halved and thinly sliced

1 ¾ pounds zucchini, cut into 1/4-inch slices (about 7 cups)

½ cup plus 1 tablespoon extra-virgin olive oil, plus more for serving

6 thyme sprigs

4 rosemary sprigs

6 garlic cloves, smashed and peeled

Fine sea salt, as needed

2 pounds eggplant, cut into 1-inch cubes (about 10 cups)

2 medium red bell peppers, sliced into 1/2-inch slices (about 3 cups)

3 cups cherry tomatoes (12 ounces)

8 ounces goat cheese, crumbled

¾ cup Castelvetrano or other good-quality olives, crushed, pitted, and torn into pieces

Lemon wedges, for serving

PREPARATION

1. Heat oven to 425 degrees, and arrange two racks in the top and bottom thirds.
2. On one rimmed 13-by-17-inch sheet pan, toss together onion slices, zucchini, 1/4 cup oil, 3 thyme springs, 2 rosemary sprigs, 3 garlic cloves and 1/2 teaspoon salt.
3. On a second rimmed baking sheet, toss together eggplant, red peppers, 1/4 cup oil, 3 thyme sprigs, 2 rosemary sprig, 3 garlic cloves and 3/4 teaspoon salt.
4. Place one tray on the top rack, and a second on the bottom rack of the oven. Roast both for 40 minutes, stirring vegetables two or three times.
5. Add tomatoes to the baking sheet with eggplant and peppers, then continue to roast until the tomatoes burst and the zucchini turn deeply golden brown, another 20 to 25 minutes. The vegetables will become very caramelized, and that’s a good thing, particularly with the zucchini and onions.
6. Transfer zucchini and onions to the baking sheet with eggplant, mix well, and spread in an even layer (it will just fit). Drizzle vegetables with another 1 tablespoon oil, then sprinkle goat cheese and olives over the top. Roast until goat cheese is soft and warmed through, 5 to 10 minutes.
7. Transfer vegetables to a serving platter, drizzle with a little more oil and squeeze juice from the one of the lemon wedges over the top. Garnish with basil leaves. Serve hot or warm, with more lemon wedges on the side.