1Heat oven to 400°. Place tortillas on ungreased cookie sheet. Bake about 5 minutes or until crisp.
2While tortillas are baking, heat oil in 10-inch nonstick skillet over medium heat. Cook onion in oil, stirring frequently, until tender; remove from heat. Stir in chicken, salsa and olives.
3Spread sour cream on tortillas. Top with chicken mixture and cheese. Bake 5 to 6 minutes, or until cheese is melted.