Heat a cast iron skillet. Meanwhile, combine spices on a plate or in a bowl. Rub all over the chicken breasts.
Warm oil over medium heat. Cook chicken until golden and heated through to an internal temperature of 165°F, around 6-8 minutes per side. Set aside to cool slightly, then shred with two forks.
While chicken is cooking, place a large pot on medium heat. Heat olive oil, then add garlic and chili powder until fragrant, around 30 seconds.
Stir in tomatoes and their juices, beans, chicken broth, water and corn. Season with salt and pepper. Bring to a boil, then reduce heat to a simmer.
Fill bowls with crumbled tortilla chips, then top with soup and desired toppings.
Store leftover soup in an airtight container in the fridge for up to one week.
Notes
Substitute rotisserie chicken to save a step in this recipe!