In a large pot on medium heat add vegetable oil and cook down diced onions, carrot, and celery for about 5 - 7 minutes ( until onion gets translucent and vegetables are a little soft). Stir frequently Add salt, pepper, paprika, and chili powder and stir for about 1 - 2 minutes Add crushed garlic, sliced leek, zucchini, and squash. Stir for about 2 - 3 minutes then add flour, stir constantly for about 1 - 2 minutes. (NOTE: if it appears to be burning, most likely it is. Either back the heat off or shorten time between steps.) Add corn, stewed tomatoes, and cilantro and stir. Slowly add chicken stock and then chicken (cleaned and stripped/chunked) and stir. Heat to a boil then reduce to simmer and cover. Let it go for about 1/2 hour ( at the very very minimum). Taste periodically and season. The longer it cooks, the better it will taste. In a separate small frying pan heat enough veggie oil (to frying temperature) in order to make sure that tortillas will be completely immersed in oil when dropped in ( cut tortillas into strips). Fry tortilla strips in oil until crisp (3-5 minutes) Remove crispy tortilla strips from oil onto a paper towel to absorb excess oil and sprinkle lightly with salt while still hot. Serve soup with a small handful of tortilla strips, sliced avocado, and sour cream ( if Desired ), also sprinkle with cheese.