How to Make It
In a colander, sprinkle the eggplant with salt and toss. Let stand for 1 hour. Transfer the eggplant to paper towels and pat dry.
Heat 2 tablespoons of the oil in a large skillet. Add the onion and cook over moderate heat, stirring occasionally, until softened, about 8 minutes. Scrape the onion into a large enameled cast-iron casserole. Repeat the process with the bell peppers, zucchini and the garlic with the eggplant, using 2 tablespoons of oil to cook each batch.
Stir the tomatoes, coriander and thyme into the vegetables in the casserole and season with salt and pepper. Cover and simmer over low heat until the tomatoes are broken down and the vegetables are very tender, about 20 minutes. Stir in the basil and serve.