How to Make It
Heat oven to 400° F. On a rimmed baking sheet, toss the tortilla strips with 1 tablespoon of the oil and ¼ teaspoon salt. Spread in a single layer and bake, tossing once, until golden and crisp, 8 to 10 minutes.
Meanwhile, heat the remaining tablespoon of oil in a large saucepan over medium heat. Add the onion and garlic and cook, stirring often, until softened, 3 to 5 minutes. Add the chipotles and cumin and cook, stirring, until fragrant, about 1 minute more.
Add the chicken broth, tomatoes (breaking them up with a spoon), ½ teaspoon salt, and ¼ pepper to the pot. Bring to a boil, add the chicken thighs, reduce heat, and simmer until cooked through, 12 to 15 minutes. Remove the chicken from the pot and, using 2 forks, shred the meat. Return the chicken to the pot and stir in the lime juice.
Serve the soup topped with the tortilla strips, Cheddar, avocado, cilantro, and lime wedges.