In a small saucepan, melt butter, over medium-low heat, and cook, swirling pan occasionally, until butter is golden brown and fragrant, about 8 minutes; let cool.
Toss together apples and lemon juice in a large bowl.
Combine flour, salt, granulated and brown sugars, and vanilla-bean seeds in another bowl, breaking up clumps and combining with a fork or fingers.
Add browned butter to apples.
Stir in flour mixture.
Rollout 1 disk of dough to just under ¼-inch thick on a lightly floured surface and fit into a 9-inch glass pie plate.
Rollout remaining disk of dough to a 13-inch round.
Rolled-out dough can be refrigerated up to 8 hours.
Be sure to let the 13-inch round sit at room temperature until pliable before topping pie, or it will break.
Place apples in pie shell, brush edges with water, and cover pie with top crust.
Trim excess, leaving a 1-inch overhang.
Fold top edge over bottom crust to seal, and crimp as desired.
Cut steam vents in top crust.
Freeze pie 30 minutes.
Meanwhile ,pre-heat oven to 425°F with rack in lowest position.
Brush pie with egg wash and sprinkle with sanding sugar.
Place a foil-lined rimmed baking sheet on floor of oven to catch any drips.
Bake pie on lowest rack 15 minutes.
Reduce oven temperature to 375°F and bake until well browned, about 1 hour.
Tent pie with foil and continue to bake until bubbling through vents, about 20 minutes more.
Remove from oven and let cool completely on a wire rack, at least 6 hours.
Pie can be made 1 day ahead and stored at room temperature.