Active time: 25 min Start to finish: 1 1/4 hr

　　

Ingredients

Makes 6 servings

　　10 tablespoons extra-virgin olive oil

　　2 lb medium tomatoes (about 6), cut crosswise into 1/2-inch-thick slices

　　About 13/4 teaspoons salt

　　1 teaspoon black pepper

　　2 lb medium red potatoes, scrubbed well

　　1 garlic clove

　　1/2 cup plain fine dry bread crumbs

　　1/4 cup finely chopped fresh basil

　　1 1/2 teaspoons chopped fresh thyme

　　

Special Equipment

a 3-qt shallow flameproof gratin or casserole dish (about 2 inches deep; not glass)

　　

Step 1

Put oven rack in middle position and preheat oven to 425°F.

　　

Step 2

Brush a shallow baking pan (1/2 to 1 inch deep) with 2 tablespoons oil. Arrange tomato slices in 1 layer in baking pan and sprinkle with a scant 1/2 teaspoon salt and 1/4 teaspoon pepper. Roast tomatoes until just tender (not falling apart), about 20 minutes.

　　

Step 3

While tomatoes roast, cut potatoes crosswise into 1/4-inch-thick slices and toss with 5 tablespoons oil in a large bowl.

　　

Step 4

Remove tomatoes from oven and put oven racks in upper and lower thirds of oven. Arrange potato slices in 1 layer in 2 shallow baking pans (1/2 to 1 inch deep) and sprinkle each pan with a scant 1/2 teaspoon salt and 1/4 teaspoon pepper. Roast potatoes, switching position of pans halfway through roasting, until tender, about 16 minutes total.

　　

Step 5

While potatoes roast, mince garlic and mash to a paste with a pinch of salt using a large heavy knife. Transfer paste to a bowl and stir in bread crumbs, basil, thyme, remaining 3 tablespoons oil, remaining 1/4 teaspoon salt, and remaining 1/4 teaspoon pepper.

　　

Step 6

Preheat broiler.

　　

Step 7

Arrange tomatoes and potatoes in 1 layer in gratin dish, alternating slices and overlapping them, and spoon any juices from tomatoes into dish. Sprinkle top with bread crumbs and broil 5 to 7 inches from heat, checking frequently after 1 minute (crumbs can brown quickly), until golden brown, about 2 minutes. Serve warm or at room temperature.

　　Cooks' note:

　　Gratin can be assembled (but not broiled) 1 hour ahead and kept at room temperature.