Getting this vegetable torte right takes a little time. You really must grill (or pan-grill) or roast all the vegetables well — they have to become quite tender — before assembling the torte. Ultimately, you want the vegetables to almost melt together. Grilling is the technique of choice because it gives the vegetables a hint of smokiness.
Coat bottom and sides of 8-inch springform pan with oil. Layer a third of the eggplant slices into bottom of the pan, then layer in half the zucchini, mushrooms, bell pepper, if using, tomato, garlic and basil, sprinkling each layer with a bit of salt and pepper. Repeat layers until all vegetable are used. Press the top with a spatula or spoon to make the torte as compact as possible. Sprinkle top with Parmesan and bread crumbs, and drizzle with about 1 tablespoon oil.
03Bake torte in oven until hot throughout and browned on top, about 30 minutes. Let sit for 5 minutes before removing outer ring of pan, then let cool for another 10 minutes before cutting into wedges.