Place chicken, tomatoes, enchilada sauce, onion, banana peppers, and garlic into slow cooker. Pour in water and chicken broth. Season with cumin, chili powder, salt, ground pepper, and bay leaf. Stir in corn and cilantro. Cover and cook on Low for 6 to 8 hours, or on High for 3 to 4 hours.
Preheat oven to 400 degrees F (200 degrees C).
Lightly coat both sides of tortillas with cooking spray. Cut tortillas into strips, then spread on a baking sheet.
Bake in preheated oven until crisp, 10 to 15 minutes. Sprinkle tortilla strips over soup.