Clean and dice eggplant, but do not peel. Sprinkle lightly with salt and set aside for 30 minutes to draw out the moisture.
In a saucepan sauté onions until softened. Add diced tomatoes with juices and cook until it thickens.
Meanwhile, rinse eggplant with hot water (removes bitterness) and pat dry with paper towels.
In a large skillet over high heat, heat the olive and vegetable oil. Quickly fry the eggplant pieces until browned.
Add the chopped celery and fry for three more minutes.
Pour in the tomato sauce, olives, capers, and salt to taste. Mix well and sauté for five minutes. Add sugar, vinegar, basil, and crushed red pepper. Lower heat; simmer for five minutes. Serve.
Notes
Serve with crusty bread for a hearty appetizer, warm or cold, as a side dish or vegetarian main dish alongside rice, mashed potatoes, or pasta.