Step 1

Preheat the oven to 375°.

Step 2

On a lightly floured surface, roll the piecrust into a 12-inch circle. Transfer to a 9-inch pie plate (no more than 1 1/4" deep). Tuck the edges under and crimp as desired. Freeze for 20 minutes. Prick the bottom of the crust 8-10 times, all over, with a fork.

Step 3

Line the frozen pie crust with parchment paper and fill with pie weights. Place on a rimmed baking sheet. Bake for 10 to 12 minutes just until the edges of the crust are dry. Carefully remove the paper with weights. Return to the oven for 3 to 5 minutes until the bottom of the crust is dry and the edges just start to turn light brown. Let cool slightly. Reduce the oven temperature to 350°.

Step 4

Place the melted butter and sugar in a medium bowl and whisk to combine. Whisk in the eggs, then flour. Add the buttermilk, lemon juice, lemon zest, vanilla extract and pinch of salt and mix to combine.

Step 5

Carefully pour the filling into the crust. Bake for 45 to 50 minutes, until the edges and center of pie are set completely.  (Tent the pie with foil towards the end if either the crust or surface of the pie look darker than golden brown). Let the pie cool completely, about 2 hours. Garnish with a sprinkle of powdered sugar, if desired.