Baked Fourth-Corner Ratatouille with Herbed Tomato Sauce

By Lauren Mitchell, Test Kitchen Director · Reviewed by AislePrompt Editorial · Published 2026-07-06 · Updated 2026-07-06

A layered vegetable casserole combining four distinct vegetables baked in a fragrant herbed tomato sauce, celebrating the fourth in a series of flavors. This mediterranean-inspired vegetarian (mediterranean) ready in about 70 minutes blends olive oil, minced garlic cloves, canned crushed tomatoes into a versatile sauce that lifts everything from grain bowls and roasted vegetables to grilled proteins — a small-batch staple worth keeping in the fridge. Each serving lands at about 200 calories and feeds 4, so a small batch covers several meals across the week without taking over the fridge. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Ingredients

• 1 medium (1 lb), sliced into 1/4-inch rounds eggplant
• 1 medium (8 oz), sliced into 1/4-inch rounds zucchini
• 1 medium (8 oz), sliced into 1/4-inch rounds yellow squash
• 1 large, sliced into strips red bell pepper
• 4 tbsp olive oil
• 3 minced garlic cloves
• 1 1/2 cups canned crushed tomatoes
• 1 tsp dried thyme
• 1 tsp dried oregano
• 1 tsp salt
• 1/2 tsp black pepper
• 1/4 cup chopped fresh basil leaves
• 1/2 cup grated Parmesan cheese
• 1 tbsp balsamic vinegar

Instructions

1. Step 1: Preheat oven to 375°F. Heat 2 tbsp olive oil in a saucepan over medium heat. Add 3 minced garlic cloves and sauté for 1 minute until fragrant. Add 1 1/2 cups canned crushed tomatoes, 1 tsp dried thyme, 1 tsp dried oregano, 1 tsp salt, 1/2 tsp black pepper, and 1 tbsp balsamic vinegar. Simmer sauce gently for 10 minutes until thickened.
2. Step 2: Lightly oil a 9-inch round baking dish with 1 tbsp olive oil. Spread the tomato sauce evenly on the bottom of the dish.
3. Step 3: Arrange alternating slices of 1 medium eggplant, 1 medium zucchini, 1 medium yellow squash, and strips of 1 large red bell pepper in concentric circles over the sauce, overlapping slightly to create a colorful layered pattern.
4. Step 4: Drizzle the remaining 1 tbsp olive oil over the vegetables, sprinkle 1/2 cup grated Parmesan cheese on top, and cover the dish with foil.
5. Step 5: Bake for 35 minutes covered, then remove foil and bake for an additional 15 minutes until vegetables are tender and cheese is golden. Garnish with 1/4 cup chopped fresh basil before serving.