What's in a name? Did you know that the only difference between a buttermilk pie and a chess pie is the method of thickening? A buttermilk pie uses flour and a chess pie uses cornmeal. We've deliberately broken the naming rules with this pie because the buttermilk is such a prominent flavor in the recipe.
In a large bowl, combine all the filling ingredients and whisk until smooth.
Pour filling into unbaked pie shell.
Bake for 80-90 minutes or until set. You'll know it's done when there only the tiniest wobble in the middle. Bake it too long and the custard will crack when cooling.
Make sure to bake your sweet potato until its very soft....it will make a smoother pie!