For the Enchilada Sauce, heat oil in a saucepan, add flour, chili powder, diced onion, minced garlic, tomato paste, roasted tomatoes, water, cumin, brown sugar, salt, and pepper. Cook until thickened.
For the Enchiladas, cook chicken with cumin, chili powder, onion, peppers, corn, garlic, green chiles, chipotle pepper, and tomatoes. Fill tortillas with the cooked mixture, roll them up and place them in a baking dish.
Pour the enchilada sauce over the rolled tortillas, top with shredded cheese, and bake until cheese is melted and bubbly.