Preheat the oven to 450°F. Roll out the dough and place into the pie pan. Trim and decorate the edges as you see fit. Prick the bottom several times with a fork. Brush lightly with one egg and a splash of milk (optional). Prebake crust for 12 minutes. Take out and set aside to cool.
Combine flour, sugar, nutmeg, cinnamon, and salt together in a medium bowl.
Put butter in a large bowl and beat until smooth and creamy. Add flour mixture and beat until evenly mixed. Add the egg yolks and beat again until fully combined. Whisk in maple syrup and whisky. Add cream and whisk mixture until smooth. Pour into prepared pie shell.
Bake for 10 minutes and then reduce the temperature to 325°F and continue to bake for 45 minutes, or until a knife or toothpick inserted into the center comes out clean. Remove pie and set aside to cool.
Allow pie to cool for at least 2 hours or overnight before serving.