Oven-Baked Ratatouille with Roasted Vegetables and Tomato Sauce

By Lauren Mitchell, Test Kitchen Director · Reviewed by AislePrompt Editorial · Published 2026-07-03 · Updated 2026-07-03

A colorful medley of zucchini, eggplant, and bell peppers baked in a rich tomato sauce with fragrant herbs. This french-inspired vegetarian (vegetarian) ready in about 60 minutes blends olive oil, medium, cut into 1-inch cubes zucchini, medium, diced yellow onion 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

• 3 tbsp olive oil
• 1 medium (about 1 lb), cut into 1-inch cubes eggplant
• 2 medium, cut into 1-inch cubes zucchini
• 1 large, cut into 1-inch pieces red bell pepper
• 1 large, cut into 1-inch pieces yellow bell pepper
• 1 medium, diced yellow onion
• 3 cloves, minced garlic cloves
• 14 oz (1 can) 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

Instructions

1. Step 1: Preheat oven to 400°F (200°C). In a large bowl, toss 1 lb cubed eggplant, 2 medium cubed zucchini, 1 large red bell pepper cut into pieces, and 1 large yellow bell pepper cut into pieces with 2 tbsp olive oil and 1 tsp salt.
2. Step 2: Spread the vegetables evenly on a large rimmed baking sheet and roast for 25 minutes until tender and lightly browned, stirring halfway through.
3. Step 3: While vegetables roast, heat 1 tbsp olive oil in a large skillet over medium heat. Add 1 diced medium yellow onion and sauté for 5 minutes until translucent.
4. Step 4: Add 3 minced garlic cloves and cook for 30 seconds until fragrant.
5. Step 5: Stir in 14 oz canned crushed tomatoes, 1 tsp dried thyme, 1 tsp dried oregano, 1/2 tsp black pepper, and simmer the sauce for 10 minutes until slightly thickened.
6. Step 6: Remove roasted vegetables from oven and transfer to the skillet with tomato sauce; stir gently to combine.
7. Step 7: Sprinkle 1/4 cup chopped fresh basil over the ratatouille, cover, and bake for an additional 10 minutes at 400°F to meld flavors before serving.