Set your oven to 350 degrees Fahrenheit. Let it get hot while you prep the filling. A steady heat is very important for eggs.

Place your unbaked pie crust into the plate. Press it down firmly against the bottom and sides. Crimp the edges with a fork for a nice look.

Crack the eggs into your large mixing bowl. Whisk them until they are light and very foamy. This adds air to the custard for lightness.

Slowly pour the sugar and flour into the eggs. Keep whisking until the mixture is thick and smooth. Make sure there are no white flour lumps.

Add the buttermilk, melted butter, and vanilla extract. Stir everything together until the color is very even. Add the tiny pinch of salt now.

Pour the liquid filling into the prepared pie crust. Fill it nearly to the top but do not spill. Carefully carry the plate to the oven rack.

Bake the pie for about forty-five to fifty minutes. The center should have a very slight jiggle. The top will look golden brown and beautiful.

Remove the pie and place it on a rack. Let it cool completely at room temperature first. This helps the custard firm up for slicing.