We may tell you the vanilla ice cream on top of this pie is optional, but you'll know what to do.
On a lightly floured surface, roll out 1 disk of pate brisee to an 1/8-inch-thick circle, about 13 inches in diameter. Drape dough over a 9-inch pie pan. Transfer pan to refrigerator, and chill 30 minutes.
Heat oven to 425 degrees. Whisk together the egg yolk and cream; set aside.
In a large bowl, toss together the apples, lemon juice, granulated sugar, flour, cinnamon, nutmeg, and salt; place in chilled bottom crust. Dot with butter.
Roll out the remaining disk of pate brisee as in step one. Brush the rim of the bottom crust with the egg wash. Place second piece of dough on top, and trim so 1 inch overhangs. Tuck the dough under, and crimp the edges with a fork or your fingers. Transfer pie to the refrigerator, and chill until firm, about 15 minutes.
Remove pie from the refrigerator, brush with the egg wash, and sprinkle generously with sugar. Cut 4 vents in the top, allowing the steam to escape.
Bake until crust begins to turn light brown, about 25 minutes. Reduce temperature to 350 degrees, and bake until golden brown and the juices are bubbling, 25 to 30 minutes. Transfer to a wire rack to cool. Serve pie with vanilla ice cream, if desired.
Use any remaining dough trimmings to make a decorative pattern on top of the pie.