Preheat your oven to 350°F (175°C). Place the unbaked 9-inch pie crust into a pie dish if it is not already in one, crimp the edges, and refrigerate the crust while you prepare the filling so it stays cold.
1 9-inch unbaked pie crust
In a medium mixing bowl, whisk together the granulated sugar, fine yellow cornmeal, all-purpose flour, and salt until evenly combined and no streaks remain.
1 1/2 cups granulated sugar, 3 tablespoons fine yellow cornmeal, 2 tablespoons all-purpose flour, 1/4 teaspoon salt
Pour the melted, slightly cooled unsalted butter into the dry mixture and whisk until the mixture looks sandy and thick. Some small clumps are fine; they will smooth out with the eggs.
1/2 cup unsalted butter
Add the eggs one at a time, whisking well after each addition, until the mixture becomes glossy and slightly thicker, forming the base of the custard filling.
3 large eggs
Whisk in the whole milk, white vinegar, and vanilla extract until the filling is completely smooth and uniform. The mixture should be pourable but slightly thickened.
1/4 cup whole milk, 1 tablespoon white vinegar, 1 teaspoon pure vanilla extract
Place the chilled pie crust on a baking sheet for easier handling. Pour the chess pie filling into the crust, leaving a small amount of space below the top edge of the crust.
1 9-inch unbaked pie crust
If your crust tends to brown quickly, loosely cover the outer edges with strips of foil or use a pie shield before baking. You can also add this halfway through baking if the crust is browning too fast.
Bake the pie at 350°F (175°C) for 40–50 minutes, until the top is golden and slightly crackly and the center is mostly set but still has a tiny jiggle when you gently nudge the pan. If the top is browning too deeply, tent the pie loosely with foil.
Transfer the baked chess pie to a wire rack and let it cool completely, at least 3 hours. The custard will continue to set as it cools, so do not cut into it while it is warm if you want clean slices.
Slice the cooled pie with a sharp knife, wiping the blade between cuts for neat slices. Serve at room temperature or chilled, with whipped cream or vanilla ice cream and a sprinkle of flaky sea salt if desired.
whipped cream or vanilla ice cream, flaky sea salt