Place the pie crust in a 9-inch pie dish and crimp the edges if desired. Set it aside.
In a large mixing bowl, using a hand mixer, combine the vegan egg replacer with sugar until well mixed.
Add the vegan butter to the mixture and continue mixing until well incorporated.
Add the vegan buttermilk, flour, vanilla extract, lemon zest, nutmeg, and salt. Mix until all the ingredients are thoroughly combined.
Pour the filling into the prepared pie crust.
Place the pie dish on a baking sheet. Bake in the preheated oven for about 60 minutes, or until the center is set and the top is golden brown.
Once baked, remove the pie from the oven and let it cool completely. Decorate with coconut whipped cream, if desired.
Notes
To store: Store vegan buttermilk pie covered in the refrigerator for up to 5 days, or transfer individual slices to an airtight container.To freeze: Buttermilk pie can be frozen for up to 3 months. To freeze the pie, wrap it tightly in plastic wrap followed by a layer of foil, or store slices in an airtight container or freezer bag. Thaw the pie overnight in the refrigerator before serving.