Take the pastry out of the fridge and let it relax a little until it is soft enough to unroll. Put it back in the fridge flat.
Melt the butter and oil in a pan over a medium heat
Add the onion and a pinch of salt and pepper and fry for 5 minutes until softening.
Add the flour and mix well so that it coats the onions.
Add half the milk and whisk over the heat until the sauce is thickened.
Take off the heat and add the remaining milk. Whisk and set aside.
Put the turkey (or chicken) and stuffing into a greased medium-sized roasting tray. Add the potatoes and bacon.
Pour the white sauce into the tray.
Dot the cranberry sauce on top.
Lay the pastry on top. If it’s not quite wide enough to reach the edges of your tin, you can use a rolling pin to roll it out slightly to increase the width.
Press your fingers along the edges all the way round, then trim the edges where needed with a sharp knife.
Brush the top all over with the beaten egg.
Put the sage, breadcrumbs and parmesan in a small bowl. Mix well, then sprinkle all over the top of the pie.
Cut a couple of small slits in the centre of the pastry to allow steam to escape.
Bake for 20-25 minutes until golden and well puffed.
Video
Notes
This pie is made using leftovers and those leftovers should only be reheated once, which happens during the cooking of the pie, so you will need to eat your pie in one sitting.