Yes, you can reheat chicken and leek pie. The best way to do this is by using an oven to maintain the crispness of the pastry. Preheat your oven to 180°C (160°C fan), cover the pie with foil, and heat for about 15-20 minutes or until the filling is piping hot. Reheating in the oven ensures the pastry stays flaky and the filling is evenly warmed.