Wash the eggplant and cut into ½ inch cubes (do not peel). Place in a colander, salt and let the eggplant sit for about an hour, this helps remove the bitterness but also to absorb less oil. In the meantime cut and prepare all your other ingredients.
Heat about 2 tablespoons of oil over medium heat in a large pan that is about 2 inches deep.
Add the eggplant and sauté until it starts to turn golden, about 5 minutes.
Add the onion and continue to sauté until soft, add the other tablespoon of oil if it is not enough.
Add oregano, olives, capers and chopped tomatoes with their juices and simmer for about 20-25 minutes.
Mix the sugar with the vinegar and pour over the pan. Heat a few minutes until you can no longer smell the vinegar.
Remove from heat, add salt and pepper to taste.
Sprinkle some chopped basil.