In a large saucepan, heat oil over medium heat. Add asparagus and onion; cook and stir until tender, 3-4 minutes.
Stir in flour, salt, garlic powder and pepper until blended; gradually stir in broth and half-and-half. Bring to a boil, stirring constantly; cook and stir until slightly thickened, 3-5 minutes. Add chicken and corn; heat through.