Place the chicken breasts in the slow cooker. Add the chicken broth, diced tomatoes with green chilies, chopped onion, minced garlic, cumin, chili powder, salt, and black pepper.
Stir in the frozen corn. Cover and cook on low for 6 hours or on high for 3 hours until the chicken is fully cooked and easy to shred.
Remove the chicken from the slow cooker. Shred it with two forks and return it to the pot. Stir to combine.
Ladle the soup into bowls. Top each serving with tortilla strips, diced avocado, chopped cilantro, and a squeeze of lime.