Heat the olive oil in a large skillet. Add the onion, garlic and salt, and sauté over medium heat until the onion is soft and translucent (5 to 8 minutes). 
Add the eggplant cubes, stir and cover. Cook until the eggplant is very well done (15 to 20 minutes), stirring occasionally. Add small amounts of additional oil, 1 tablespoon at a time, if needed to prevent sticking. 
Stir in tomato paste and vinegar, and heat to the boiling point. Add the olives and remove from heat.
Stir in the artichoke hearts, then cool to room temperature. Taste to adjust the seasonings, adding the optional herbs, if desired. 
Cover tightly and chill. Serve cold or at room temperature.

TUNISIAN EGGPLANT -- From "Still Life With Menu" by Mollie Katzen ?(recipe re-printed with author's permission)