In slow cooker, combine shredded chicken, whole tomatoes (hand crushing to break them into smaller pieces), enchilada sauce, green chilies, onion, and garlic. Add chicken broth, water, and spices. Stir in corn. Cover and cook on LOW for 6-8 hours, or on HIGH for 3-4 hours. Remove bay leaf before serving.
Meanwhile, preheat oven to 400 degrees. Lightly brush both sides of tortillas with vegetable oil. Cut tortillas into strips and spread on baking sheet. Bake, turning occasionally, until crisp; about 5-10 minutes. Use to garnish soup.