In small bowl, mix chili powder, salt, pepper and cayenne; sprinkle evenly over both sides of chicken breasts.
In a 10-inch skillet, heat the oil over medium heat. Add the chicken; cook 3 to 4 minutes, turning once, until juice of chicken is clear when center of thickest part is cut (170°F).
Stir in onion and peppers, cook an additional 2 minutes. Add the black beans, corn and salsa. Heat to boiling. Reduce heat. Cover and simmer 2 to 4 minutes or until vegetables are hot. Serve over rice with fresh cilantro.