Makes: 4 servings. Prep: 10 minutes. Cook: 22 minutes.
Heat broiler. Drizzle lime juice over chicken; sprinkle with 1 teaspoon of the chili powder. Coat broiler pan with nonstick cooking spray. Broil chicken 5 to 6 minutes per side or until 160° F on an instant-read thermometer. Remove and set aside.
Heat oil in large, deep pot over medium heat; add garlic and remaining teaspoon of chili powder. Cook 1 minute. Add tomatoes (with their juice), broth and 1 cup water; bring to a boil, reduce heat to medium-low and cook 10 minutes, covered.
Tear chicken into small pieces and divide among four bowls. Divide tomato broth among the bowls; top each with cheese, avocado and tortilla pieces.