In a medium bowl, combine flour and salt. Then, add the cold butter and blend with your fingers or use a pastry cutter until it resembles coarse crumbs.

Add ice water, one tablespoon at a time, until the dough starts to come together. Form it into a disk, wrap it in plastic wrap, and let it chill in the fridge for at least 30 minutes.

Peel and cut sweet potatoes into chunks. Cook them in boiling water until tender, about 15-20 minutes. Drain and mash until smooth.

In a large bowl, mix the mashed sweet potatoes, sugar, salt, cinnamon, nutmeg, and ginger until well combined.

Then, add the eggs, melted butter, buttermilk, and vanilla extract. Stir until everything is smooth and creamy.

Preheat your oven to 350°F (175°C). Roll out the chilled dough into a circle, about 12 inches wide, and transfer it into a 9-inch pie pan.

Pour the sweet potato filling into the crust and smooth out the top.

Bake the pie for about 50-60 minutes. A knife inserted into the center should come out clean. If the edges brown too quickly, cover them with foil.

Let the pie cool completely on a wire rack.

Serve as-is or add whipped cream on top with a sprinkle of cinnamon or nutmeg.