Buttermilk Pie

Description
A favorite in the American South, this pie has a filling of buttermilk, butter, eggs, flour and sugar, plus flavorings like lemon juice, vanilla and nutmeg. It is similar to but tangier than chess pie.
 * Serves 8

Cornmeal Crust

 * 1¼ cups flour, plus more for dusting the work surface
 * ¼ cup cornmeal
 * ½ teaspoon salt
 * 8 tablespoons (1 stick) cold sweet cream salted butter
 * 5 tablespoons water

Filling

 * 5 tablespoons sweet cream salted butter, at room temperature
 * ¾ cup sugar
 * 2 large eggs, separated
 * 2½ tablespoons flour
 * 1 cup buttermilk
 * ½ tablespoon freshly squeezed lemon juice
 * ¾ teaspoon finely grated lemon zest
 * ⅛ teaspoon ground mace
 * ¼ teaspoon salt
 * 3 tablespoons sugar

Cornmeal Crust

 * 1) Combine the dry ingredients and butter in a food processor or use a bowl and a pastry cutter; pulse or mix until the mixture resembles coarse bread crumbs.
 * 2) Add the water a few tablespoons at a time, using just enough until a dough is formed.
 * 3) Wrap in plastic wrap and refrigerate until firm, at least 1 hour.
 * 4) Preheat oven to 350°F.
 * 5) Have ready a 9-inch pie pan and pie weights for blind baking the crust.
 * 6) On a lightly floured work surface, roll out the dough to a ⅛-inch-thick circle and transfer to the pie pan, trimming edges to fit.
 * 7) Allow to rest in the refrigerator for at least 30 minutes (or freeze for later use).
 * 8) Line the chilled pie shell with aluminum foil or parchment paper and weigh it down with pie weights or uncooked beans.
 * 9) Bake for 20 minutes or until light golden brown.

Filling

 * 1) While the crust is baking, make the filling: in the large bowl of a stand mixer or hand mixer, combine the butter and ¾ cup sugar on medium speed for about 5 minutes, until light and fluffy.
 * 2) Add egg yolks one at a time, incorporating after each addition.
 * 3) Reduce the speed and add the flour in increments, mixing well.
 * 4) Slowly add the buttermilk, lemon juice, zest, mace, and salt, missing well.
 * 5) The mixture will form curds, set aside.
 * 6) In the bowl of a stand mixer or hand mixer, combine the egg whites and salt on medium speed.
 * 7) Beat for a few minutes until frothy, then slowly add 3 tablespoons of sugar, increasing the speed to high and beating until stiff peaks form.
 * 8) Gently fold the egg-white mixture into the buttermilk mixture and pour it into the pie crust.
 * 9) Bake for 45 – 50 minutes, or until the surface is brown and barely jiggles.
 * 10) Can be served with fresh berries or whipped cream.