Preheat the oven to 180°C.
Add the cooked chicken, beans, tomato paste, diced tomatoes, capsicum, cooked onions, corn and taco seasoning to a large casserole dish.
Mix everything together until well combined.
Sprinkle the grated cheese evenly over the top.
Add a layer of corn chips over the cheese. Or leave the chips off and just heat the casserole up and serve the chips on the side.
Bake uncovered for approximately 20–25 minutes, or until the filling is piping hot and the cheese has melted.
Serve with extra corn chips, sour cream, sliced spring onions and avocado, if using.