Preheat the oven to 180°C.
Mix the chicken, mayonnaise, soup, onion, curry powder, salt, pepper, and half the cheese in a large bowl.
Spoon the mixture into a greased ovenproof dish.
Sprinkle the remaining cheese on top.
Crush the potato chips and scatter them over the cheese if using.
Bake for 25–30 minutes until golden and bubbling.
Let it rest for 5 minutes before serving.