I follow a really straight forward recipe, it's by Jamie Oliver and I use it regularly, except for a few tweaks here and there. For my pie leave out the chestnuts and sage and part boil some firm potatoes (I used Kipfler) before you get started on the filling.
If you want to give it a go follow Jamie’s recipe (minus the sage and chestnuts) and before you stick the pastry top on, chuck your part boiled potatoes into the mix to make it more of a one pot wonder. Stick it in the oven to cook through and Bob’s your Uncle… or should that be Jamie? Serve with extra veggies if you like or you could have it on it’s own. Mr Oliver would be proud.