Layered Baked Ratatouille with Herbed Tomato Sauce

By Lauren Mitchell, Test Kitchen Director · Reviewed by AislePrompt Editorial · Published 2026-06-13 · Updated 2026-06-13

A vibrant vegetable medley of zucchini, eggplant, and bell peppers baked in a fragrant herbed tomato sauce, showcasing tender layers and rich Mediterranean flavors. This mediterranean-inspired vegetarian (mediterranean) ready in about 60 minutes blends large, thinly sliced red bell pepper, large, thinly sliced yellow bell pepper, olive oil 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 180 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

• 2 medium, sliced into 1/4-inch rounds zucchini
• 1 medium, sliced into 1/4-inch rounds eggplant
• 1 large, thinly sliced red bell pepper
• 1 large, thinly sliced yellow bell pepper
• 4 tbsp olive oil
• 1 medium, finely chopped yellow onion
• 3, minced garlic cloves
• 14 oz canned crushed tomatoes
• 1 tsp fresh thyme leaves
• 6 leaves, chopped fresh basil leaves
• 1/2 tsp dried oregano
• 1 tsp, divided salt
• 1/2 tsp, divided black pepper
• 1/4 cup grated Parmesan cheese
• 1 tbsp, chopped (for garnish) fresh parsley

Instructions

1. Step 1: Preheat the oven to 375°F. In a medium skillet, heat 2 tbsp olive oil over medium heat. Add 1 finely chopped yellow onion and 3 minced garlic cloves, sautéing for 5-6 minutes until the onion softens and becomes translucent and fragrant.
2. Step 2: Stir in 14 oz canned crushed tomatoes, 1 tsp fresh thyme leaves, 6 chopped fresh basil leaves, 1/2 tsp dried oregano, 1/2 tsp salt, and 1/4 tsp black pepper. Simmer the sauce over low heat for 10 minutes until thickened and aromatic.
3. Step 3: Lightly brush a 9-inch round baking dish with 1 tbsp olive oil. Spread the herbed tomato sauce evenly on the bottom.
4. Step 4: Arrange the sliced vegetables—2 medium zucchini rounds, 1 medium eggplant rounds, 1 large red bell pepper slices, and 1 large yellow bell pepper slices—in alternating overlapping layers vertically, standing them upright to create a colorful pattern.
5. Step 5: Drizzle the remaining 1 tbsp olive oil over the layered vegetables, then sprinkle the top with 1/2 tsp salt and 1/4 tsp black pepper.
6. Step 6: Cover the baking dish tightly with aluminum foil and bake at 375°F for 30 minutes until the vegetables are tender but still hold their shape.
7. Step 7: Remove the foil, sprinkle 1/4 cup grated Parmesan cheese over the top, and bake uncovered for another 10 minutes until the cheese melts and turns golden.
8. Step 8: Remove from oven, let cool for 5 minutes, then garnish with 1 tbsp chopped fresh parsley before serving.