In a pan over medium heat, toast the chile(s) a little, turning constantly, until you can detect a whiff of strong chile.
In a pan of water just off the boil, place the chile(s) in the water; you can cut the corner of the chile(s) to help them stay under the water. Soak for 15–20 minutes.
Carefully de-vein and de-seed the chile(s) and chop roughly.
Place the chile(s), onion, garlic, tomatoes and one cup of stock in a blender.
Puree the ingredients and strain through a sieve.
Add the rest of the chicken stock and season to taste.
Cut two of the tortillas into thin strips and the rest into small squares. Heat the oil on a pan and over high heat fry the tortilla strips until they’re coloured and crispy. Do the same with the squares and place them on paper towels to soak up any oil.
When you’re ready to serve, prepare the garnishes.
Serve the soup in the bowls and add some tortilla strips to add a little texture and sprinkle with a little coriander/cilantro to make it pretty. If you’re feeling creative you can also finish with a little flourish of sour cream.
Serve with plenty of cold beer or a spicy, icy Michelada.