Preheat the oven to 350 degrees F. In a mixing bowl, combine the flour, salt, and 2 tablespoons sugar. Add the lard and work it in with your hands until the mixture resembles coarse crumbs. Add the water, 1 tablespoon at a time. Form the dough into a smooth ball. Wrap the dough in plastic wrap and refrigerate for 30 minutes. In a large saute pan, over medium heat, melt the butter. Stir in the brown sugar and cook for 1 minute. Add 1/2 teaspoon cinnamon and apples. Saute for 3 minutes. Remove from the heat and turn into a deep dish 9-inch pie pan. Remove the dough from the refrigerator and place on a lightly floured surface.
Roll out the dough into a circle about 12 inches in diameter and 1/8-inch thick. Gently fold the circle of dough in half and then in half again, so that you can lift if without tearing it, and place over the pie pan. Crimp the edges of the pastry. Brush the pastry with the egg wash. Using a sharp knife, make a 1-inch circle in the center of the pie. Place in the oven and cook for 15 minutes. In a mixing bowl, whisk the remaining 1/4 cup sugar, cream, yolk, and vanilla extract. Pour the custard through the hole in the pie. Place back in the oven and continue to cook for 30 minutes, or until the custard is set. Remove from the oven and cool completely. Sprinkle the top of the pie with powdered sugar. Spoon onto serving plates, garnish with whipped cream and serve.
Recipe adapted from Irish Country Cooking by Darina Allen, published by Viking Penguin, 1996