Spicy Chicken Tortilla Soup

INGREDIENTS
1 medium onion, chopped (about 1 cup)
2 garlic cloves, minced (about 2 teaspoons)
2 tablespoons vegetable oil
4 ounce can green chilies, chopped
15 ounce can Italian-style stewed tomatoes, 
     chopped, reserving the juice
4 cups Chicken Broth or canned reduced-sodium chicken broth
1 teaspoon lemon pepper
2 teaspoons Worcestershire sauce
1 teaspoon chili powder
1 teaspoon ground cumin
1/2 teaspoon hot sauce or to taste
4 tablespoons all-purpose flour
1/2 cup water
1 pound skinless boneless chicken breast, cut into small cubes
1/3 cup  sour cream Salt and pepper to taste
Tortilla Strips 
Shredded Mozzarella cheese for garnish

DIRECTIONS
In a large saucepan, cook the onion and the garlic in the oil over moderately low heat for 5 minutes or until the onion is softened. Add the chilies, tomatoes with their juice, broth, lemon pepper, Worcestershire, spices, and hot sauce and simmer the mixture for 20 minutes.

In a small bowl, combine the flour with the water and whisk it into the soup. Bring the soup back to a boil and simmer for 5 minutes. Add the chicken and simmer for 5 minutes or until it is just cooked through. Stir in the sour cream and salt and pepper to taste, and garnish each portion with the tortilla strips and shredded mozzarella cheese.