Peel, core, and thinly slice all the apples, keeping them as even as can.
In a bowl, toss the apples with sugar, cinnamon, nutmeg, salt, and lemon juice.
Place the unbaked pie crust into the pie dish and smooth it into the edges.
Spoon the apple mixture into the crust, piling it slightly in the center.
In another bowl, mix flour, brown sugar, cinnamon, and salt, then blend in the cold butter until it looks sandy.
Sprinkle the crumb mixture generously over the apples, covering them completely.
Place the pie on a sheet pan to catch any drips.
Bake at 375°F (190°C) for 45–55 minutes, until the topping turns golden and the apples bubble underneath. Let the pie rest so the juices can settle and the slices hold their shape.
I serve it slightly warm, sometimes with vanilla ice cream or a spoonful of whipped cream. The warm apples and cool topping melt together perfectly.