Preheat oven to 375°F (190°C).

Roll out the pie crust and place in a 9-inch dish. Line with parchment, add pie weights, and bake for 15 minutes.

Remove parchment and weights, then bake an additional 5 minutes until lightly golden. Set aside.

In a saucepan, heat milk and cream with cinnamon and vanilla until steaming. Do not boil.

If using whole spices, remove from heat and steep for 10 minutes, then discard the cinnamon stick or vanilla bean.

In a separate bowl, whisk eggs, sugar, and salt until smooth and pale. Add nutmeg or orange zest if using.

Slowly pour the warm milk mixture into the eggs while whisking constantly to temper the mixture.

Strain custard through a fine-mesh sieve for extra smoothness.

Lower oven to 325°F (160°C).

Pour custard into the pre-baked crust.

Bake for 35–40 minutes, until the edges are set but the center still jiggles slightly.

Cool at room temperature. Refrigerate at least 2 hours before slicing.