6 tablespoons cooking oil
8 6- inch corn tortillas, halved and cut crosswise into 1/4-inch strips
1 onion, chopped
4 large cloves garlic, smashed (or equivalent pre-chopped)
1 tablespoon paprika
2 teaspoons ground cumin
1 teaspoon ground coriander
1 teaspoon chili powder
1/4 teaspoon cayenne
1 1/2 quarts water
3 cups canned crushed tomatoes in thick puree (one 28-ounce can)
2 1/2 teaspoons salt
1 3/4 pounds boneless, skinless chicken breasts, cut into 3/4-inch pieces
1. In a large heavy pot, heat the oil over moderately high heat. Add half the tortilla strips and cook, stirring, until pale golden, about 1 minute. Remove with a slotted spoon and drain on paper towels. Repeat with the remaining tortilla strips.
2. Reduce the heat to moderately low. Add the onion, garlic, and spices; cook, stirring, for 5 minutes. Add the broth, tomatoes, salt, cilantro leaves, if using, and one-third of the tortilla strips. Bring to a simmer. Cook, uncovered, for 30 minutes; Add avocado.
3. In a blender, puree the soup in batches; pour it back into the pot. Add the chicken, bring the soup back to a simmer, and cook until just done, about 1 minute. Stir in the avocado.
4. To serve, put the remaining tortilla strips in bowls, top with the cheese, and pour in the soup. Sprinkle with the chopped cilantro, if using, and serve with the lime wedges.
Notes: Be very careful when blending this soup. I exploded the first batch in my blender and burned myself. If you have an immersion blender (which I have now added to my Christmas list) this won’t be a problem, but if you are using a regular blender, I would strongly suggest allowing it to cool in addition to getting a towel to put over the top of the blender.
