Place the chicken breasts in a large pot with the homemade chicken broth, diced onion, and minced garlic. Bring to a simmer over medium heat.
Add the chili powder, cumin, salt, and pepper. Cook for 20 minutes until the chicken is fully cooked.
Remove the chicken from the pot, shred it with two forks, and return it to the broth.
Stir in the diced tomatoes and lime juice. Simmer for 10 more minutes to blend the flavors.
While the soup simmers, spread the tortilla strips on a baking sheet and bake at 375°F for 10 minutes until crisp.
Ladle the soup into bowls and top each serving with baked tortilla strips, chopped cilantro, and lime wedges.