Place chicken broth in a large saucepan or Dutch oven; add chicken breasts. Bring to boiling. Reduce heat and simmer, covered, about 15 minutes or until chicken is tender and no longer pink. Remove chicken from broth. Let stand until cool enough to handle. Skin, bone, and and finely shred chicken; set chicken aside. Discard skin and bones. Strain broth through a large sieve or collander lined with 2 layers of 100% cotton cheesecloth. Skim fat from broth and set broth aside. In the same saucepan cook onion, cumin, and garlic in the 1 tablespoon hot oil until onion is tender but not brown. Stir in strained broth, undrained tomatoes, tomato sauce, chili peppers, cilantro, and oregano. Bring to boiling. Reduce heat and simmer, covered, for 20 minutes. Stir in shredded chicken; heat through. Meanwhile, cut tortillas in half, then cut crosswise into 1/2 inch wide strips. In a heavy medium skillet heat 1/4 inch oil. Fry strips in hot oil, about half at a time, about 1 minute or until crisp and light brown. Remove with a slotted spoon; drain on paper towels. Divide fried tortilla strips among four soup bowls. Ladle soup over tortilla strips. Sprinkle each serving with shredded cheese. Serve immediately. Makes 4 servings.