Preheat the oven to 200C /400F and brush a large baking sheet with olive oil.
Cut the eggplants in half or quarters depending on the size (or a mix of both) and brush all sides with olive oil. Season them well with salt & pepper and spread them out cut side down on the baking tray. Roast for about 30 – 40 minutes until golden in colour and are cooked through. Turn over once or twice halfway through.
While the eggplants are roasting, heat a glug of olive oil in a large non-stick frying pan and fry the onions, pepper, and celery until soft. About 5 minutes. Add a splash of water if they start to stick. Add the tomato paste and a little more of the water and cook for a minute or two until the water has cooked off. Add the tin of tomatoes, sultanas and sugar and cook for about 5 minutes. Add whatever water is left.
Add the vinegar, capers, olives, and chilli and cook for about 5 minutes seasoning with a little salt and pepper. Allow this to cool to room temperature.
When the eggplants are roasted, remove them from the oven and allow them to cool. Place on a serving platter and spoon over the caponata. Crumble the feta over if you are using it and sprinkle the toasted pine nuts and basil leaves.
Serve with crusty bread and a salad or with any meat or fish dish. This is perfect for a BBQ/braai.