My mother's buttermilk pie is a family favorite. I've added fruit and tweaked it just a bit and now we have another favorite for the table. I have tried fruit other than blueberries - raspberries, strawberries, blackberries - but everyone loves the blueberries best. Using fresh farm eggs with their bright yellow yolks gives the filling a lovely buttery color. Using a whisk for mixing gives the filling a lighter texture.