Drain artichoke hearts, reserving liquid. Cut artichoke hearts into bite-size pieces; set aside.
Rinse chicken; pat dry. Cut into cubes and set aside.
In a large skillet cook and stir zucchini and sweet pepper in hot oil until crisp-tender; remove from skillet. Add mushrooms and green onions to skillet. Cook and stir until just tender; remove from skillet.
In the same skillet cook chicken, half at a time, for 2 to 3 minutes or until no longer pink. Return all chicken to skillet. Stir in reserved artichoke hearts and liquid, tomatoes, olives, vinegar, garlic powder, seasoned salt, oregano, and basil. Combine cornstarch and water; add to skillet. Cook and stir until thickened and bubbly. Cook and stir 1 minute more. Return all vegetables to skillet; stir until combined.
Place bread shell on a lightly greased or parchment-lined baking sheet. Top with chicken mixture. Sprinkle with mozzarella cheese and Parmesan cheese.
Bake in a 425 degree F oven for 10 to 12 minutes or until mozzarella cheese melts and pizza is heated through. Let stand 5 minutes before serving. Makes 6 servings.