In 4-quart saucepan, heat oil over medium-high heat. Cook and stir onion, garlic and chicken in oil 3 to 5 minutes or until chicken is no longer pink in center.
Stir in chowder, beans, chiles, oregano, cumin and pepper flakes. Heat to boiling. Reduce heat to low; simmer 10 to 15 minutes, stirring occasionally.
Top each serving with 2 tablespoons cheese and the cilantro.