Cook pasta according to package directions. Drain and set aside.
Lightly coat a large saucepan with cooking spray; heat over medium heat. Add onion; cook about 3 minutes or just until tender. Add garlic; cook for 1 minute more. Stir in tomatoes, artichokes, chicken, and olives. Cook and stir about 5 minutes or until heated through. Stir in cooked penne, tossing gently to heat through. Sprinkle with salt and pepper. Top with fresh mozzarella cheese and basil.