Best Apple Pie

Ingredients

• Salt
• Butter
• Sugar
• Lemon juice
• Water
• Granulated sugar
• Brown sugar
• Egg
• Cornstarch
• Cinnamon
• Lemon
• Flour
• Vanilla
• Juice
• Half
• Vanilla bean
• Ice water

Directions

1. Pulse the flour, sugar, and salt in a food processor until evenly mixed. Add the butter and run the machine until the biggest butter bits are no larger than peas, then tip everything into a large bowl. In a small bowl, stir the vinegar into ½ cup ice water. Pour it over the flour mixture while using a fork to pull the dough together. When shaggy pieces form, knead the mixture in the bowl a couple of times with your hands, just enough to gather it; it will still look dry, clumpy, and crumbly. Move the larger clumps to a work surface. Sprinkle 1 Tbsp. ice water over what remains in the bowl, knead again until it comes together, and add it to the dough on the counter. Take half of the dough, press it into a cohesive mass while working in any dry bits, then pat it into a ¾"-thick square. Cut it into 4 pieces with a bench scraper or knife. Stack the pieces, tucking any stray dry bits between the layers, and press down to bring them together. Shape this portion into a ¾"-thick disk, wrap it snugly in plastic, and repeat with the remaining dough. Refrigerate for at least 2 hours.
2. Make-ahead note: the dough may be prepared 5 days ahead and kept chilled, or frozen up to 1 month.
3. In a large bowl, toss the apples with the brown sugar, granulated sugar, lemon juice, cinnamon, salt, allspice, and cardamom until coated. Let them sit until their juices begin to collect, at least 1 hour and up to 3 hours.
4. Let the dough stand at room temperature for 5 minutes so it softens slightly. Roll the disks one at a time on a lightly floured surface to ⅛" thick. Layer the rounds on a parchment-lined baking sheet with parchment between them, then chill them while you prepare the filling.
5. Pour the apple cider into a medium saucepan. Scrape in the vanilla bean seeds, add the pod, and bring the cider to a boil. Cook, whisking occasionally, until reduced by two-thirds. Drain the juices from the bowl of apples into the cider. Bring it back to a boil and cook until reduced to about ½ cup, then remove the vanilla pod. In a small bowl, stir the cornstarch with 3 Tbsp. water until dissolved, then whisk it into the cider. Cook, whisking constantly, until the mixture is bubbling and very thick, about 1 minute. Let it cool slightly, then scrape it over the apples and toss to coat.
6. Gently move a dough round into the pie dish. Lift the edges so the dough can settle down into the dish without stretching; if it is too cold to bend easily, let it warm a bit. Press the dough firmly against the bottom and sides, then trim it to leave about 1" overhang. Beat the egg with 1 tsp. water in a small bowl, and brush it over the dough edges. Scrape in the apple filling, piling it higher in the center, then dot the filling with butter. Set the remaining dough round over the filling. Trim the top round so it has a ½" overhang. Fold the bottom edge up and over the top edge, pressing to seal. Crimp the edge, brush the top with the remaining egg wash, sprinkle with demerara sugar, and cut a few vents in the top. Place the pie on a foil-lined rimmed baking sheet and chill it in the freezer for 10 minutes. Preheat the oven to 375 degrees.
7. Bake for 1½–2 hours, until the pastry is a deep golden brown and thick juices are bubbling through; yes, it may take the full 2 hours. Set the pie on a wire rack and let it cool at least 4 hours before serving.
8. Make-ahead note: the pie may be made 1 day ahead. Let it cool, then store it covered with foil at room temperature.