Preheat the oven to 350° Fahrenheit.

In a food processor, blitz together the butter, flour, sugar, vanilla extract, and salt until a dough is created.

Press the dough into the pan until evenly spread and cover the entire dish. Line with parchment on top and use weights (or pennies) to fill the pie dish.

Bake for 12-15 minutes, or until golden brown. Let cool completely.

Whisk gelatin into the water and let sit for 5 minutes.

In a saucepan, combine sugar, cornstarch, salt, and eggnog. Cook over a low heat until the solids dissolve.

Bring to a boil and cook while stirring for 2 minutes. The mix should thicken slightly. Sitr in the gelatin / water mixture until the gelatin is dissolved.

Remove from heat and stir in vanilla extract. Set aside to cool.

In a large bowl, whip the heavy whipping cream until light and fluffy.

Fold whipped cream into the cooled eggnog mixture. Pour the mixture into the crust and let set until firm.

Dust with cinnamon, nutmeg, or powdered sugar.