1. Preheat the oven to 350.
2. Place the chicken breasts skin side up on a sheet pan and rub with olive oil; sprinkle with salt and pepper, and roast for 35 to 40 minutes.
3. When chicken has cooled down enough to touch, discard the skin and bones, and shred the meat. Cover and set aside.
4. Heat 3 tablespoons of olive oil in a large pot or a Dutch oven.
5. Add in onions, celery and carrots and cook over medium-low heat for 10 minutes.
6. Add in garlic and cook for 30 seconds.
7. Add in chicken stock, tomatoes with their puree, jalapenos, cumin, coriander, a tablespoon of salt (depending on the saltiness of the chicken stock), a teaspoon of pepper, and cilantro.
8. Cut the tortillas in half and then cut them crosswise into half-inch strips. Add to the soup.
9. Bring the soup to a boil and lower the heat and let simmer for 25 minutes.
10. Mix in the shredded chicken and season to taste.
11. Serve hot.

NOTE: have sliced avocado, sour cream, grated Cheddar cheese, and tortilla chips ready for serving.