For the crust:
¾ cups/450g all-purpose flour, more for dusting surfaces
1½ tsp kosher salt
½ tsp sugar
340g cold unsalted butter (3 sticks), cut into large dice
For the filling:
About 10 cups/1.2kg peeled and sliced apples, more as needed
½ cup/100g granulated sugar
½ tsp salt
1 tsp cinnamon
Pinch freshly grated nutmeg
1/2 teaspoon allspice
1 to 2 tsp freshly squeezed lemon juice or 1 tbs unfiltered apple cider vinegar
1 to 2 tbs Calvados or other apple liqueur, brandy or cider
½ cup/70g all-purpose flour
2 tbs/30g cold butter, cut into small pieces
2 tsp coarse or granulated sugar for sprinkling
Make the crust:
In a food processor or stand mixer, mix together the flour, salt and sugar.
Add butter and pulse (or mix at medium-low speed) until the pieces are coated with flour.
Add ½ cup ice water and mix until incorporated. Keep dribbling in ice water, a tablespoon at a time, mixing until the dough just comes together into a lump. It should be moist, but not sticky.
Turn out on to a lightly floured surface. (If dough feels wet, use a little extra flour.)
Press the dough together, turning over a few times, until smooth and solid.
Shape into 2 disks, using about 1/3 of the dough for the top crust and the remaining 2/3 for the bottom crust.
Wrap separately in plastic wrap and refrigerate at least 1 hour and up to 2 days.
On a lightly floured surface or non-stick baking mat, roll out the larger disk to about ½cm thickness.
The size and shape will depend on your dish. Use the crust to line a large 2½ - to 3-litre baking dish, like a 25cm round or 23cm square, at least 5cm deep.
Refrigerate while you prepare the apples.
Make the filling:
In a large mixing bowl, combine the apples, sugar, salt, cinnamon, nutmeg, allspice, lemon juice or vinegar, and flour.
Toss together until the apples are roughly coated with what looks like wet sand.
Roll out remaining dough to ½cm thickness (or a bit less) and lay it gently over the fruit.
Trim any excess and fold the edges into a thick rim. Crimp, if desired.
Whisk the egg thoroughly with 1tbs cold water.
Brush over the entire top crust, including the edges.
Cut 5 or 6 vents on top.
Refrigerate pie while the oven heats.
Place a baking sheet on the middle rack of the oven and heat to 220ºC.
Place pie on baking sheet and bake for 20 minutes. Reduce heat to 200ºC.
Bake another 25 minutes.
Open the oven and carefully sprinkle the sugar over the surface of the pie.
Bake about 10 minutes longer.
Look for steam and bubbling juices coming out of the vents, and a well-browned crust, before removing the pie from the oven.
Let cool at least 1 hour before serving.
Delicious served hot or cold, as is, or with custard or cream.