Preheat the oven to 375°F (190°C). Separate one egg white and lightly beat it. Brush the unbaked pie crust with the beaten egg white to create a barrier that prevents sogginess. Place the crust in the oven and pre-bake for 7–8 minutes. Remove from the oven and allow it to cool for 10 minutes.

In a large mixing bowl, combine 3 whole eggs, the reserved yolk from the separated egg, and the remaining beaten egg white. Whisk until smooth. Add the sugar, salt, vanilla extract, heavy cream, and milk, and whisk again until fully combined. The mixture should appear silky and uniform.

Pour the custard filling into the pre-baked pie crust, ensuring an even distribution. Lightly sprinkle the ground nutmeg over the surface of the custard for a classic finishing touch.

Place the pie in the preheated oven and bake for 35–45 minutes, or until a knife inserted into the center comes out clean. The custard should still have a slight jiggle, as it will continue to set while cooling. If the crust edges begin to brown too quickly, cover them with aluminum foil to prevent burning.

Allow the pie to cool completely on a wire rack. Once cooled, transfer it to the refrigerator to chill for at least 2 hours before serving. Chilling enhances the pie’s silky texture and ensures clean slices.