I want to make a homemade chicken pot pie but I would like to top it with mashed potatoes and then put a regular crust on top of that can that be done what would be the cooking temperature or time difference if any
2 Answers
Generally such a concoction (topped with mashed potatoes) is called a Shepherds Pie, but adding a crust... I have no idea what to call that ;-)
When cooking a pot pie everything is already cooked prior to putting it in the baking dish, except the crust.
So all you really need to do is make sure your crust is cooked to your desired done-ness. The mashed potatoes might keep the bottom of the crust a little wetter but really it should not require much more than you usually would bake it for, if any. It depends on how hot you bake your pot-pies.
I usually cook them at 425F so I get a nice brown on my crust and it is about 15 - 20 minutes, but that will depend on your crust recipe. I would follow the crust recipe baking instructions and add maybe 5 minutes.
You can then try the pot pie and adjust the backing duration according to your personal preference.
If the ingredients of the pie touch the bottom of the crust, you don't have a vent hole (to allow the steam to escape) and the heat isn't sufficient to bake through the pastry, you will end up with a very soggy, tough crust.
I would ensure all the ingredients have cooled down before assembling the pie, and ensure there is some gap between the mash and the pastry, ensuring there is a vent in the crust and bake accordingly to the package instructions (if shop bought), or as normal until golden and the pie filling is heated through.
A better result might be achieved using cooked, sliced, potatoes on top of the filling rather than mash though.