Make the Pie Crust:

1. Preheat the oven to 325ºF and place an oven rack in the lower part of the oven.
2. In a medium bowl, mix together the cookie crumbs, melted butter, sugar, and salt. The crumb mixture should be like wet sand. If it feels too dry, add in more melted butter as needed. And conversely, if it’s too wet, add additional cookie crumbs.
3. Pour the crumbs into a 9-inch pie plate and start pressing the ingredients up the sides of the pie plate to form the edges first. Once the edges are formed, work the crumbs down to evenly distribute them into the bottom of the pie plate, then stamp it down. Place the pie crust in the freezer.

Make the Filling, Assemble, and Bake:

1. In a large bowl, use a rubber spatula to mix together the mascarpone, sugar, cinnamon, vanilla extract, and salt.
2. Whisk in the cream and eggs until smooth.
3. Transfer the filling to the prepared crust. Bake for 45-55 minutes on the lower rack, or until the outer 2-½ inches is slightly puffed and the filling is set.
4. Remove the pie from the oven and transfer to a wire rack to cool to room temperature. Transfer to the refrigerator to finish setting up, at least 6 hours or overnight.
5. Serve cold with whipped cream.