Eggplant, Zucchini, and Tomato Stacks

¾ c olive oil
3 yellow onions, chopped
Salt and freshly ground pepper, to taste
6 garlic cloves, minced
1/4c fresh basil leaves, cut into thin strips
1/2 Tbsp. minced fresh oregano
1/4 cup chopped fresh parsley
1 eggplant, 2 1/2 to 3 inches in diameter, sliced 1/8 inch thick
5 tomatoes, sliced 1/4 inch thick
4 zucchini, halved crosswise and sliced lengthwise 1/8 inch thick
1/2 cup grated Parmigiano-Reggiano cheese

Preheat an oven to 425°F. In a large sauté pan over medium-high heat, warm 6 Tbs. of the olive oil. Add the onions, salt and pepper and cook, stirring occasionally, until soft, about 5 minutes. Add the garlic and cook 5 minutes longer. Add the basil, oregano and parsley and cook for 2 minutes more. Remove the pan from the heat. Coat the bottom of a 12-heavy frying pan with olive oil. Place 8 eggplant slices in a single layer in the pan and season with salt. Top each with 1 tsp. onions and 1 tomato slice and season with salt. Top each with 1 tsp. onions and 2 zucchini slices and season with salt. Top each with 1 tsp. onions. Repeat the layering 2 more times, ending with the zucchini. Drizzle each vegetable stack with 1 tsp. olive oil. Bake until the vegetables are tender, about 40 minutes. Sprinkle each stack with 1 Tbs. cheese and bake for 7 to 10 minutes more. Let the vegetables rest for 5 minutes before serving. Serves 8.