Preheat the oven to 350°F (175°C). Place the pie crust in a 9-inch pie dish and prick the bottom with a fork.

Bake the crust for 10 minutes until lightly golden. Remove from the oven and set aside to cool.

In a saucepan over medium heat, combine the milk, sugar, and salt. Stir until the sugar dissolves and the mixture is warm, but not boiling.

In a mixing bowl, whisk together the eggs, vanilla extract, and ground cinnamon.

Slowly pour the warm milk mixture into the egg mixture, whisking continuously to temper the eggs.

Pour the custard filling into the pre-baked pie crust.

Bake the pie in the preheated oven for 30-35 minutes, or until the custard is set and a knife inserted in the center comes out clean.

Remove from the oven and allow to cool to room temperature before refrigerating for at least 2 hours.

Slice the pie and serve with whipped cream on top, garnished with a sprinkle of ground cinnamon.