3 1/2- to 4-pound chicken
large yellow onion, quartered
whole black peppercorns
avocados, thinly sliced
tortilla chips, plus more for serving
- Rinse the chicken inside and out and pat it dry with paper towels. Place the chicken in a large pot.
- Cut 3 of the carrots and 2 of the celery stalks into 1-inch pieces. Quarter the onion. Add the cut vegetables to the pot with the salt, peppercorns, and enough cold water to cover (about 8 cups). Bring to a boil. Reduce heat and simmer, skimming any foam that rises to the top, until the chicken is cooked through, about 30 minutes. Transfer the chicken to a bowl and let cool.
- Strain the broth, discarding the vegetables. Return the broth to the pot.
- Thinly slice the remaining carrots and celery. Add them to the broth and simmer until tender, about 10 minutes.
- Meanwhile, when the chicken is cool enough to handle, shred the meat and add it to the soup.
- In each bowl, place a small handful of tortilla chips and the slices from 1/2 an avocado. Ladle some of the soup into each bowl and top with more chips, if desired.