Make the sauce base

• Sauté the onion and garlic until soft
• Add the tomatoes and cook until tender
• Add the roasted red peppers, salt and black pepper
• Let it cook well

Blend the sauce

• Blend the mixture until smooth

Assemble the ratatouille

• Pour the sauce into a baking dish
• Arrange the sliced vegetables on top
• Add salt and drizzle with olive oil

Bake

• Cover and bake until the vegetables are tender