1. In a large pot, cook the onion in oil on medium heat for about 5 minutes. Add the bell peppers, and cook for 10 more minutes.

  2. Incorporate the zucchini and aubergine, and cook for 10 more minutes, until they’ve softened.

  3. Add the can of tomatoes, turn down the heat and let simmer for a while—an hour is a good start. Periodically taste the ratatouille and adjust the seasoning with salt, pepper, and provence herbs.