Preheat the oven: preheat the oven to 180°C / 350-375°F / Gas Mark 4-5.
Enchilada filling: add the cooked chicken, diced onion, black beans and corn to a large mixing bowl and stir to combine.
Season: net sprinkle the salt, pepper, garlic powder, onion powder and smoked paprika into the bowl and stir to combine.
Baking dish: spray a large baking dish with olive oil and then pour in a tablespoon of the enchilada sauce and use a spatula to spread this across the base of the dish.
Fill and roll: working one mini soft tortilla at a time use an ice cream scoop to spoon the combined chicken mixture into the tortillas and then roll to close. As you roll each tortilla, place it into the base of the prepared baking dish. Then repeat for all 12 tortillas.
Sauce and extra topping: next pour the rest of the enchilada sauce over the top of the enchiladas and spread this out to cover each one. Then transfer the leftover chicken filling over the top and spread this out to cover.
Cheese: top the dish with the cheese.
Oven bake: place the uncovered baking dish into the preheated oven on the middle shelf. Bake the enchiladas for 20 minutes.
Cooked: once the cook time is up and the cheese has melted with visible little brown bits across the top use a pair of oven mitts to remove the baking dish and and set it on a heatproof surface.
To serve: garnish the enchiladas with the chopped cilantro. Plate and serve with pickled red onions, avocado and Greek yogurt.