3 cups (750 ml) Cortland apples, peeled, cored and sliced
3 cups (750 ml) McIntosh apples, peeled, cored and sliced
Milk for brushing
In a food processor, pulse the flour, sugar and salt until combined. Add the butter and pulse for several seconds until the butter pieces are the size of peas. Add the water. Pulse for several seconds more until the dough just begins to hold together, adding more water if necessary. Remove the dough and shape into 2 discs.
On a floured surface, roll the dough into two thin 28-cm (12-inch) discs. Line a 23-cm (9-inch) Pyrex pie plate with one of the discs, leaving any dough that overhangs. Cut a slit in the middle of the other disc. Refrigerate for 30 minutes.
With the rack in the lowest position, preheat the oven to 190°C (375°F).
In a large mixing bowl, combine the brown sugar and flour. Whisk in the marmalade. Add the apples and stir with a spatula to coat well.
Pile the filling in the pie shell. Brush the edge of the pastry with milk. Cover with the second piece of dough. Trim the excess dough from the edge of the pie with a sharp knife. Seal tightly by pressing the two layers of dough together with a fork or your fingers. Brush the top lightly with milk.
Bake until juice from the filling is bubbling in the centre of the pie, about 1 hour. Let cool before serving.