No Pressure Cooker - see directions at the bottom of the page.
Cut 4 of the tortillas into 1/4-inch wide strips. Roughly chop the remaining 4 tortillas.
Press the saute' button on an electric pressure cooker. When hot, add 1 teaspoon of the oil and half of the tortilla strips. Cook, stirring occasionally, until crisp, 10 - 12 minutes. Transfer to paper towels. Repeat with 1 teaspoon of the oil and remaining tortilla strips.
To the pressure cooker (still on saute'), add the remaining 1/2 teaspoon oil and the garlic. Cook, stirring, until fragrant, about 1 minute. Add the chopped tortillas, chicken broth, tomato sauce, chicken, beans, corn, chipolte peppers, cumin, chili powder, salt, and black pepper to taste.
Seal and cook on high pressure for 20 minutes, until the chicken is tender and cooked. Quick or natural release, then open when the pressure subsides. Shred the chicken well with two forks (do this in the pot).
Ladle 1 1/2 cups of soup into each serving bowl. Divide the tortilla strips, avocado, red onion (if using), and cilantro among the bowls to serve. Squeeze 1 lime wedge over the soup before eating.