Heat a large pan over medium-high heat. Fry the onion, garlic and peppers together in a splash of olive oil. Season with the taco/enchilada seasoning, oregano, chilli flakes, salt and pepper.
Combine the cooked rice with shredded chicken, cheese, corn, black beans and peppers mixture in a large, deep casserole dish. Season with salt, pepper and more taco/enchilada seasoning and mix well.
Top with more cheese then bake for 15-20 minutes until the cheese is golden and the casserole is hot throughout.
Remove from the oven then top with sour cream, avocado, coriander/cilantro and chillies. Serve with lime wedges.