For the Tortilla Strips:
In a large Dutch oven, heat the oil over medium-high heat. In two batches, add the tortillas strips and cook until crispy, about 1 minute. Remove with a slotted spoon and drain on paper towels. Sprinkle with 1/8 teaspoon salt.
For the Chicken Soup:
Return the pot to medium heat. Add the onion, garlic, and jalapeno. Cook, stirring frequently, until the onion is softened, about 4 minutes. Add the broth, tomatoes, beans, corn, chicken, chili powder, cumin, salt, and pepper. Bring to a boil. Reduce the heat to medium-low and continue simmering for 25 minutes, stirring occasionally.
Remove from the heat. Remove the chicken and shred.
Return the pot to medium-low heat. Stir the shredded chicken back into the pot. Stir in the lime juice. Simmer for an additional 5 minutes. Serve the soup with shredded cheese, sour cream, avocado, and cilantro, if desired.
Notes
Decrease the amount of jalapeno if you want the soup less spicy.
When cutting the jalapeno, make sure to remove the seeds before adding them to the pot. You can wear gloves to avoid your hands feeling tingy.
If you have leftover rotisserie chicken, you can shred it to add to the soup instead of cooking the chicken breasts in the tortilla soup. You will need approximately 3 to 4 cups of shredded chicken. You can even simmer the soup with some rotisserie bones to add more flavor to the soup.
If you want to thicken the soup, you can whisk some masa harina with the soup before pouring it back into the soup. Masa harina gives a distinctive corn flavor to the soup. A cornstarch slurry will thicken the soup if you don’t have any masa harina.