Prepare the Crust

1. Combine Dry Ingredients: In a large bowl, mix together the flour, sugar, and salt.
2. Cut in the Butter: Add the cold, cubed butter to the flour mixture. Using a pastry cutter or your fingers, work the butter into the flour until the mixture resembles coarse crumbs.
3. Add Ice Water: Gradually add ice water, one tablespoon at a time, mixing until the dough comes together.
4. Chill the Dough: Divide the dough into two equal parts, shape into discs, wrap in plastic wrap, and refrigerate for at least 30 minutes.

Prepare the Filling

1. Mix the Apples: In a large bowl, combine the sliced apples with sugar, cinnamon, nutmeg, flour, and lemon juice. Toss to coat the apples evenly.
2. Let it Sit: Allow the mixture to sit for about 10 minutes to release some juices.

Assemble the Pie

1. Preheat Oven: Preheat your oven to 425°F (220°C).
2. Roll Out the Dough: On a floured surface, roll out one disc of dough into a circle about 12 inches in diameter. Transfer it to a 9-inch pie plate.
3. Add the Filling: Pour the apple mixture into the crust, spreading it evenly. Dot with small pieces of butter.
4. Top Crust: Roll out the second disc of dough and place it over the filling. Trim any excess dough, then crimp the edges to seal. Cut slits in the top crust to allow steam to escape.
5. Brush and Sprinkle: Brush the top crust with a bit of melted butter or egg wash, and sprinkle with sugar if desired.

Bake the Pie

1. Bake: Bake in the preheated oven for 15 minutes, then reduce the temperature to 350°F (175°C) and continue baking for an additional 30-35 minutes, or until the apples are tender and the crust is golden brown.
2. Cool: Remove from the oven and let the pie cool for at least 15 minutes before slicing.