This soup is from Mexico's Yucatan.
I found this recipe as I've been putting together a little "chicken soup from around the world" collection for one of my aunts. Right now she needs all the healing properties, potions, and prayers she can get.
This one from Mexico caught my eye. I'm afraid I can't share where its from, because I have only its xeroxed copy (Gourmet or Bon Apetit, most likely.)
sopa de lima
8 C chicken broth
1/2 C fresh lime juice (2.5 of my limes)
1 medium onion, chopped
*2-4 serrano or other hot chilies, seeded and chopped (to taste)
2 garlic cloves, finely chopped
3/4 lb chicken breasts or thighs, trimmed of fat and diced
2-3 large vine-ripened tomatoes, seeded and diced
4 corn tortillas, cut into 1/2-in strips
a couple Tbs fresh cilantro leaves
*Since I didn't have the chilies on hand, I used a teaspoon of dried red pepper flakes. It added a bit of kick, but I'm sure the chilies would have so much more depth of flavour. Next time.
In a large pot, combine chicken broth and lime juice. Bring to a boil. Reduce heat to low and simmer while you prepare the onions. In large non-stick skillet, heat oil over medium-high heat. Add onion and cook, stirring often, until its translucent and beginning to brown (5 minutes.) Stir in chilies (or red pepper flakes) and garlic; cook until mixture is brown and aromatic (1-2 minutes). Add a ladleful of the hot broth to the skillet, stir, then pour the contents of the skillet into the simmering broth. Add chicken pieces, tomatoes, and salt to taste to the broth. Simmer gently until the chicken is cooked thoroughly (about 5 minutes). Remove from heat.
Meanwhile, preheat oven to 375 degrees. Set tortilla strips on a baking sheet and bake for 3-5 minutes, until crisp. Place a few strips in the bottom of each serving bowl. Ladle the soup into bowls and garnish with cilantro leaves. Don't be tempted to skip the garnish! It adds so much great flavour. Enjoy!