Place flours, baking powder, butter and 1/4 cup sugar in a food processor . Process until mixture resembles fine breadcrumbs. Add egg yolk and 1/4 cup cold water. Process until pastry just comes together. Turn pastry onto a lightly floured surface. Knead until smooth. Wrap in plastic wrap. Refrigerate for 30 minutes until firm.
Meanwhile, make apple filling. Place apples and 1/3 cup cold water in a saucepan. Bring to the boil. Reduce heat to medium-low. Simmer, covered for 5-7 minutes or until apples are tender. Drain. Return apples to the pan. Stir in sugar, cinnamon and lemon juice. Set aside.
Preheat oven to 180oC or 160oC fan-forced. Grease a 3-cm deep, 20cm base pie dish.
Place two-thirds of the pastry between 2 sheets of baking paper. Roll out into a 30 cm round. Line base and sides of prepared dish with pastry. Trim edges. Spoon in filling. Brush edge with a little egg-wash. Place remaining pastry between two sheets of baking paper. Roll out until large enough to cover the dish. Cover filling with pastry. Press edges together. Trim excess.
Make two cuts on the top of the pie to allow steam to escape. Brush with remaining egg wash. Sprinkle with remaining sugar. Bake for 40 to 45 minutes or until golden. Serve with cream.