Cut the chicken into bite-sized pieces and season well with salt and pepper.
In a Dutch oven or large heavy-duty saucepan heat the oil over medium heat. Add the chicken and turn every 2 - 3 minutes to cook on all sides. Remove to a plate and cover with foil.
Add the remaining tablespoon oil to the pan and saute the onion, pepper and garlic with a few dashes salt and pepper. Cook until soft, stirring often about 7 - 8 minutes.
Add the chicken back to the pan with the oregano and toss with the veggies.
Stir in the tomatoes, enchilada sauce, black beans and corn with ¼ teaspoon salt and ⅛ teaspoon black pepper.
Bring to a slow simmer and cook 30 minutes, stirring often. Taste and season with more salt and pepper as needed.
Serve with a sprinkle of cheese, a dollop of sour cream and a handful of chips for scooping and dunking.