In a large saucepan over a medium heat, warm the oil then add the onion, chillies and garlic then cook and stir until soft, about 4 to 6 minutes. Stir in masa harina, stock, turkey, enchilada sauce, black beans, sweetcorn, cumin, chilli powder and paprika. Bring to the boil and simmer for 5 to 10 minutes.
Just prior to serving stir in the cream and the salt to taste. Ladle the soup into warmed bowls and top with sliced avocado, grated cheese, soured cream, chopped fresh coriander and tortilla chips. Serve.
You may not be able to find a poblano chilli in you local shops. Try searching in specialty shops or substitute with a green chilli in a pinch.