Making a sweet potato pie from scratch starts with the crust. Make the sweet potato pie crust by mixing 13 ounces of flour, 1/2 teaspoon of salt and 2 1/2 teaspoons of sugar in a large mixing bowl. Add two sticks of butter to the bowl, and combine.
Mix in 6 tablespoons of water one at time until the butter-flour mixture turns into dough. Separate the dough into two evenly sized disks. Wrap each disk in plastic wrap, and refrigerate them for 20 minutes. Fit the dough disks into separate aluminum pie pans.
Make the sweet potato pie filling by mixing together 2 cups of peeled-and-cooked sweet potatoes, 1 cup of sugar, 1/2 stick of melted butter, two eggs, 1 teaspoon of vanilla extract, 1/4 teaspoon of salt, and 1/4 teaspoon each of ground cinnamon and ginger. Mix the ingredients together until the mixture is smooth. Add 1 cup of milk, and continue to stir the mixture until the milk is completely incorporated.
Pour the mixture into the pie crust dough, and bake it for 45 minutes at 350 degrees Fahrenheit. Insert a knife or toothpick into the center of the pie to check if it is finished baking. If the knife comes out clean, then the pie is finished.