Coat a skillet with oil and season the chicken with salt and black pepper.
Brown the chicken on 7 minutes per side over a moderate heat or until it is no longer pink inside.
Sprinkle the garlic powder, Mexican spices, and cumin over the chicken before turning it over.
Let it cool. Sauté the garlic and onion in the chicken drippings until soft, then add the chilies and corn, stirring well to combine.
Add the stewed tomatoes and cook for a minute.
Shred the chicken with your fingers, and then add it to the pan with the vegetables.
Dust the mixture in the pan with some flour and stir briefly.
Preheat the oven to 350 degrees F.
Microwave the tortillas for half a minute on high, to make them more pliable.
Coat the bottoms of a pair of 9 x 13 inch pans with a ladleful of the enchilada sauce, and then dip each tortilla into this sauce on both sides, to coat them lightly.
Spoon ¼ cup of the chicken mixture into each tortilla, and then fold the tortillas over the filling.
Put 8 rolled up, filled tortillas in each pan, seam side down.
Top with the rest of the enchilada sauce and the shredded cheddar cheese.
Bake the enchiladas for 15 minutes or until the cheese melts.
Garnish them with chopped tomatoes, sour cream, cilantro and chopped scallions if you like, before serving.
Serve these chicken cheese enchiladas with refried beans and Spanish rice.