Roasted-Vegetable Lasagne

Preparation Put oven racks in upper and lower thirds of oven and preheat oven to 425°F. Cut 3 (1/3-inch-thick) lengthwise slices from center of eggplant and reserve remainder for another use. Brush 2 large shallow baking pans with 1 tablespoon oil total, then arrange eggplant, zucchini, and bell peppers in 1 layer in pans. Brush vegetables with remaining 2 tablespoons oil and sprinkle with pepper and 1 1/4 teaspoons salt. Roast, switching position of pans halfway through roasting, until eggplant and zucchini are browned and tender, 15 to 20 minutes total, then transfer eggplant and zucchini to a plate. Turn peppers over and continue to roast until tender, about 10 minutes more. Transfer peppers to a bowl and cover, then let stand 10 minutes. Meanwhile, move 1 rack to middle position and leave oven on. Peel peppers. While vegetables roast, cook garlic in butter in a 1 1/2- to 2-quart heavy saucepan over moderate heat, whisking frequently, until fragrant, about 30 seconds. Whisk in flour and cook, whisking constantly, 2 minutes. Add milk in a slow stream, whisking, and bring to a boil, whisking constantly. Reduce heat and simmer, whisking frequently, 8 minutes (sauce will thicken slightly when it first comes to a boil). Remove from heat and cool béchamel sauce, stirring occasionally, 10 minutes. Stir in cheeses, basil, and remaining 1/2 teaspoon salt. Soak noodles in hot water just until pliable, 8 to 10 minutes. Spread 2/3 cup sauce in an 8-inch square baking dish. Drain 1 large noodle or 2 small noodles on a clean kitchen towel (not terry cloth) and put over sauce in dish. Top with half of zucchini in 1 layer, 1/2 cup sauce, and another noodle (or 2). Make another layer with all of eggplant, 1/2 cup sauce, and another noodle (or 2), and another with all of bell peppers, 1/2 cup sauce, and another noodle (or 2). Top with remaining zucchini, 1/2 cup sauce, and another noodle (or 2). Cover completely with remaining sauce. Bake until golden and bubbling, 25 to 30 minutes. Let stand in pan on a rack 20 minutes. Cooks' notes:·Vegetables can be roasted and peppers peeled 1 day ahead and chilled, covered. ·Sauce can be made 1 day ahead. Cover surface with wax paper and chill. Rewarm over low heat, stirring often, before using.

Preparation Put oven racks in upper and lower thirds of oven and preheat oven to 425°F. Cut 3 (1/3-inch-thick) lengthwise slices from center of eggplant and reserve remainder for another use. Brush 2 large shallow baking pans with 1 tablespoon oil total, then arrange eggplant, zucchini, and bell peppers in 1 layer in pans. Brush vegetables with remaining 2 tablespoons oil and sprinkle with pepper and 1 1/4 teaspoons salt. Roast, switching position of pans halfway through roasting, until eggplant and zucchini are browned and tender, 15 to 20 minutes total, then transfer eggplant and zucchini to a plate. Turn peppers over and continue to roast until tender, about 10 minutes more. Transfer peppers to a bowl and cover, then let stand 10 minutes. Meanwhile, move 1 rack to middle position and leave oven on. Peel peppers. While vegetables roast, cook garlic in butter in a 1 1/2- to 2-quart heavy saucepan over moderate heat, whisking frequently, until fragrant, about 30 seconds. Whisk in flour and cook, whisking constantly, 2 minutes. Add milk in a slow stream, whisking, and bring to a boil, whisking constantly. Reduce heat and simmer, whisking frequently, 8 minutes (sauce will thicken slightly when it first comes to a boil). Remove from heat and cool béchamel sauce, stirring occasionally, 10 minutes. Stir in cheeses, basil, and remaining 1/2 teaspoon salt. Soak noodles in hot water just until pliable, 8 to 10 minutes. Spread 2/3 cup sauce in an 8-inch square baking dish. Drain 1 large noodle or 2 small noodles on a clean kitchen towel (not terry cloth) and put over sauce in dish. Top with half of zucchini in 1 layer, 1/2 cup sauce, and another noodle (or 2). Make another layer with all of eggplant, 1/2 cup sauce, and another noodle (or 2), and another with all of bell peppers, 1/2 cup sauce, and another noodle (or 2). Top with remaining zucchini, 1/2 cup sauce, and another noodle (or 2). Cover completely with remaining sauce. Bake until golden and bubbling, 25 to 30 minutes. Let stand in pan on a rack 20 minutes. Cooks' notes:·Vegetables can be roasted and peppers peeled 1 day ahead and chilled, covered. ·Sauce can be made 1 day ahead. Cover surface with wax paper and chill. Rewarm over low heat, stirring often, before using.