In a food processor, combine flour, sugar and salt.

Add butter and pulse to form small pea sized pieces.

While pulsing, slowly add buttermilk just till dough forms together. Add a drop more milk if too dry.

Lay out on floured surface and divide into 2 disks.

Chill 1 hour.

Roll out one crust and lay in 9 inch pie pan.

Add 4 cups of your apple pie filling.

Roll out second crust and cut strips.

Lay across pie to create lattice and brush with egg wash (egg plus drop water.)

Sprinkle on sugar.

Bake at 425 for 20 mins then lower to 375 and bake until bubbling, approx 40-50 mins. Cover edges with foil if getting too brown.

Cool a few hours and serve with ice cream and whipped cream.