Finely dice the onion, garlic, peppers, and celery and add them to a crockpot.
Also add in the chicken breasts, canned tomatoes, bay leaves, cumin seeds, dried chiles, and chicken stock. The stock should just cover all the ingredients.
Cover and set the crockpot on low. Cook for 6-8 hours.
Remove dried chiles and bay leaves and discard. Remove chicken breasts, shred, and return to crockpot.
Add in cilantro sprigs, corn, and a few corn tortillas cut into bits. Let the crockpot simmer for another 30-60 minutes.
Season soup with salt and pepper.
To make tortilla strips, dice corn tortillas into strips and bake at 350 degrees for 15-20 minutes until lightly browned and crispy.
Serve soup piled high with tortilla strips. Other fun garnishes include lime wedges, crumbled cotija cheese, avocados, and sour cream.