In a large saucepan, saute the onion, celery and pepper in oil for 3-4 minutes or until crisp-tender. Add chicken and garlic powder; cook for 4-5 minutes or until chicken juices run clear. Stir in salsa.
Combine cornstarch and water until smooth; gradually stir into chicken mixture. Bring to a boil; cook and stir for 2 minutes or until thickened and bubbly. Add the parsley, salt and hot pepper sauce. Serve with pasta.