Sauté onion, garlic, crushed red pepper, tomato paste and a few fresh thyme leaves in olive oil. Add 28 oz can San marzano tomatoes (crushed-or diced then broken up w masher). Summer uncovered 10-15 minutes.
Place sauce in the bottom of baking dish. Layer sliced eggplant, zucchini, yellow squash, and tomato. Drizzle w olive oil, salt and fresh cracked pepper. Bake covered 350 for 30 min. Uncover at 375 for 15. Broil if desired to brown for a few. Rest for 5-10 minutes. Serve w simple salad and crusty bread, or a simple protein (grilled fish or chicken), or over polenta or linguini with freshly grated parmigiano reggiano. Perfect summer meal.