1 pound Japanese eggplant, cut diagonally into 1/4-inch-thick slices
1 pound zucchini, cut diagonally into 1/4-inch-thick slices
Cooking spray
1 pound large beefsteak tomatoes, peeled, seeded, and cut into 1/4-inch-thick slices
1 1/2 tablespoons extra-virgin olive oil, divided
1/4 teaspoon salt, divided
1/4 teaspoon freshly ground black pepper, divided
4 ounces French bread baguette
1 cup (4 ounces) grated fresh Parmigiano-Reggiano cheese
2 tablespoons chopped fresh flat-leaf parsley
2 teaspoons chopped fresh oregano
1 1/2 teaspoons chopped fresh thyme
2 garlic cloves, minced
1/4 cup fat-free, less-sodium chicken broth