Pre-boil the potatoes for 10 minutes, depending on their size, with or without the skin. You can peel it later. You want them to be semi-cooked but not so soft they break. They will continue cooking in the oven.
Add the parchment paper to your baking dish, if you want, and layer one roll of pastry dough.
You can use pie weights and blind bake it for 10 mins in a pre-heated oven at 180 degrees Celsius. This step is optional, but I like to do it to let the pie bottom cook from the inside.
Take the pie out of the oven, and let it rest for 5 minutes.
Peel and slice your potatoes, and add one layer on top of the pie crust you just baked.
Season with salt and pepper.
Add dollops of tomato passata, but don't coat it or it will be too runny.
Season with oregano and drizzle some Belmorso EVOO, about a tablespoons or 2.
Top with the scamorza or provola cheese slices.
Then layer the Italian cotto ham slices.
Finish with the pre-grated parmesan cheese.
Cover your Italian ham and cheese pie with the second roll of pie pastry.
Use a fork to fold the sides neatly, and to punch a few holes on the top of the pie. This will help it cook on the inside.
You can bake your pie in a pre-heated oven at 180 degrees Celsius for 30 minutes. I suggest using a lower level of the oven for the first 20 minutes, and then transferring to the top so it can take some colour and crunch up.
Take out of the oven and serve. Since it's a high calorie recipe, I suggest one quarter each. You can serve with a salad, roasted vegetables, or a side of soup.