Preheat oven to 400°F

Combine 1/4 cup cheese and next 7 ingredients (through chiles, in a large bowl, stirring just until moist. Pour mixture into a 13X9 inch baking dish coated with cooking spray.

Bake at 400°F for 15 minutes or until set. Pierce entire surface liberally with a fork; pour enchilada sauce over top. Top with chicken; sprinkle with remaining 3/4 cup cheese. Bake at 400°F for 15 minutes or until cheese melts. Remove from oven let stand 5 minutes. Cut into 8 pieces; top each serving with 1 tablespoon sour cream