optional: black olives, saffron, smoked chillies, sun-dried tomatoes
Split the eggplant lengthwise, place in a colander, and sprinkle with salt to draw out the bitterness. Set aside for 30 minutes, drain and cut into 2cm cubes.
Heat the oil in a heavy-bottomed or cast iron pan. Add the eggplant and cook until lightly browned. Remove and set aside. In the same pan, cook the zucchinis the same way.
In the same pan, cook the onion (add more oil if necessary) until translucent. Add the red and green capsicums and cook until tender; add garlic, eggplant, zucchini, tomato and tomato puree. Cook for 1 minute.
Pluck the rosemary and thyme leaves, and add to the ratatouille. Add optional ingredients, if using. Simmer over low heat for 1 hour.
Alternatively, you can cook it in the oven at 180°C for 40 minutes, then at 150°C for another 40 minutes.
Season to taste with sugar, salt and pepper. Remove from heat, allow to cool and refrigerate if not using immediately. The flavours will develop overnight. Serve warm or cold, as a side dish, as a topping, or use as a base or flavouring for other recipes.