A summer tomato gratin should burst with concentrated, bright tomato flavor and contrasting firm texture from the bread, but most recipes lead to mushy results. Not this one.
Starting our gratin on the stovetop initiated the breakdown of the tomatoes, drove off some moisture that would otherwise have sogged out the bread and shortened the overall cooking time. We finished the dish in the dry, even heat of the oven.
Toasting large cubes of a crusty artisan-style baguette ensured that the bread didn’t get too soggy once combined with the tomatoes. After toasting the bread, we added the coarsely chopped tomatoes along with garlic, a small amount of sugar, and salt and pepper.
Just before moving the skillet to the oven, we folded in most of the toasted bread and scattered the remainder over the top along with some Parmesan to create a crusty, savory topping that contrasted with the custard-y interior.
A scattering of fresh basil provided color and bright flavor. The success of this recipe depends on using ripe, in-season tomatoes. Do not use plum tomatoes, which contain less juice than regular round tomatoes and will result in a dry gratin.
You can serve the gratin hot, warm or at room temperature. You will need a 12-inch oven-safe skillet for this recipe.
BEST SUMMER TOMATO GRATIN
Start to finish: 1 hour, 15 minutes
6 tablespoons extra-virgin olive oil
6 ounces crusty baguette, cut into 3/4-inch pieces (4 cups)
3 garlic cloves, sliced thin
3 pounds ripe tomatoes, cored and cut into 3/4-inch pieces
2 teaspoons sugar
1 teaspoon salt
1 teaspoon pepper
11/2 ounces Parmesan cheese, grated (3/4 cup)
2 tablespoons chopped fresh basil
Adjust an oven rack to the middle position, and heat the oven to 350 degrees.
Heat 1/4 cup oil in a 12-inch oven-safe skillet over medium-low heat until shimmering. Add the bread, and stir to coat. Cook, stirring constantly, until bread is browned and toasted, about 5 minutes; transfer to a bowl.
Cook remaining 2 tablespoons oil and garlic in the now-empty skillet over low heat, stirring constantly, until garlic is golden at edges, 30-60 seconds. Stir in the tomatoes, sugar, salt and pepper. Increase heat to medium-high, and cook, stirring occasionally, until tomatoes have started to break down and have released enough juice to be mostly submerged, 8-10 minutes.
Off heat, gently stir in 3 cups of the bread until completely moistened and evenly distributed. Using a spatula, press down on bread until completely submerged. Arrange remaining 1 cup bread evenly over surface, pressing to partially submerge. Sprinkle evenly with Parmesan.
Transfer skillet to oven, and bake until top of gratin is deeply browned, tomatoes are bubbling and juice has reduced, 40-45 minutes. After 30 minutes, run spatula around edge of skillet to loosen crust and release any juice underneath. (Gratin will appear loose and jiggle around outer edges but will thicken as it cools.)
Remove skillet from oven, and let sit for 15 minutes. Sprinkle with basil, and serve.
Nutrition information per serving: 301 calories; 148 calories from fat; 16 g fat (3 g saturated, 0 g trans fats); 6 mg cholesterol; 740 mg sodium; 31 g carbohydrate; 4 g fiber; 7 g sugar; 8 g protein.