Add the chicken broth to a large pot along with the chicken breasts. Season with 2 teaspoons of Tex Mex seasoning and bring to a boil over high heat. Cover with a lid, turn the heat down to low, and simmer for 15 to 20 minutes or until the chicken is cooked through.
Remove the chicken from the pot and set aside to rest for 5 minutes.
Add the salsa to the broth and bring back to a simmer. Season with more Tex Mex seasoning, if needed.
Using two forks, shred the chicken and add back into the pot.
Serve the soup topped with chopped cilantro or sliced green onions.
