A fresh tomato gratin that showcases the very best of summer tomatoes
Published in America's Test Kitchen
Some think it’s sacrilege to cook a perfect summer tomato, but we disagree. Cooking intensifies the tomato’s natural flavor, and it’s an excellent way to use good tomatoes at the time of year when there are plenty of them around.
Tomato gratin (sometimes called scalloped tomatoes) is a great cooked-tomato dish because it combines fresh tomatoes with bread to soak up all the juices released as the tomatoes cook. But if you use the wrong type of bread or treat it incorrectly, you can end up with a mushy mess. And that’s a fate we can’t accept for in-season tomatoes.
Knowing how important the choice of bread was, we tried breadcrumbs, sandwich bread and a supermarket baguette, which all fell short. It was when we tried an artisan-style baguette that things really started to look up. With its resilient open crumb and chewy texture, it could soak up the tomatoes’ juices without falling apart, and its crisp crust offered nice textural contrast.
We took two more steps to prevent the bread from getting too soggy: We cut it into large 3/4-inch chunks, and then we toasted them in a skillet with plenty of olive oil, which had the benefit of giving this otherwise lean dish some richness as well as balancing the tomatoes’ acidity.
We set the bread aside before adding the tomatoes to the pan and cooking them to drive off some of their moisture. We then folded the bread back in just before transferring the skillet to the oven. This lessened the time it sat in the juices, so it wouldn’t turn mushy. And for more crunchy contrast, we toasted another cup of bread, bringing the total to 4 cups, so that I’d have enough to scatter over the surface before sprinkling on the Parmesan.
The results were perfect: The gratin had a soft, tender interior and a nicely crunchy, flavorful topping. For a boost of flavor, we browned some thinly sliced garlic in the skillet before adding the tomatoes. And with a sprinkle of chopped basil over the top of the gratin once it came out of the oven, we had a fresh take on tomato gratin that showcased the very best of summer tomatoes.
Best Summer Tomato Gratin
Serves 6 to 8
6 tablespoons extra-virgin olive oil
6 ounces crusty baguette, cut into 3/4-inch cubes (4 cups)
3 garlic cloves, sliced thin
3 pounds tomatoes, cored and cut into 3/4-inch pieces
2 teaspoons sugar
1 teaspoon salt
1 teaspoon pepper
1 1/2 ounces Parmesan cheese, grated (3/4 cup)
2 tablespoons chopped fresh basil
1. Adjust the oven rack to the middle position and heat the oven to 350 F. Heat 1/4 cup oil in a 12-inch ovensafe skillet over medium-low heat until shimmering. Add bread and stir to coat. Cook, stirring constantly, until bread is browned and toasted, about 5 minutes. Transfer bread to a bowl.
2. Return the now-empty skillet to low heat and add remaining 2 tablespoons of oil and the garlic. Cook, stirring constantly, until garlic is golden at the edges, 30 to 60 seconds. Add tomatoes, sugar, salt and pepper and stir to combine. Increase heat to medium-high and cook, stirring occasionally, until the tomatoes have started to break down and have released enough juice to be mostly submerged, 8 to 10 minutes.
3. Remove the skillet from the heat and gently stir in 3 cups of bread until completely moistened and evenly distributed. Using a spatula, press down on the bread until it is completely submerged. Arrange remaining 1 cup of bread evenly over surface, pressing to partially submerge. Sprinkle evenly with Parmesan.
4. Bake until the top of the gratin is deeply browned, tomatoes are bubbling, and juice has reduced, 40 to 45 minutes; after 30 minutes, run a spatula around the edge of the skillet to loosen the crust and release any juice underneath. (Gratin will appear loose and jiggle around outer edges but will thicken as it cools.)
5. Remove the skillet from the oven and let stand for 15 minutes. Sprinkle gratin with basil and serve.
Recipe notes: For the best results, use the ripest in-season tomatoes you can find. Supermarket vine-ripened tomatoes will work, but the gratin won’t be as flavorful as one made with locally grown tomatoes.
Do not use plum tomatoes, which contain less juice than regular round tomatoes and will result in a dry gratin.
For the bread, we prefer a crusty baguette with a firm, chewy crumb. You can serve the gratin hot, warm or at room temperature.
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