Preheat oven to 400 degrees F after preparing the eggplants.
Brush eggplant lightly with olive oil. Saute or grill until lightly browned. Place in a 9×13 baking dish. Set aside.
Saute diced chicken and onion in a large skillet over medium heat. Stir in tomato paste and water, cover skillet, reduce heat to low and simmer for 10 min.
Pour chicken/tomato mixture over eggplant. Season with oregano, salt and pepper and cover with aluminum foil.
Bake in the preheated oven for 20 min.