- Preheat oven to 425°F.
Prepare the pie crusts: Roll one piece of dough into a 13-inch circle and transfer it to a 9-inch pie plate. Refrigerate until ready to fill. Roll the second piece into a 12-inch circle, cover, and refrigerate while prepping the filling.
- Combine the dry ingredients—sugar, flour, nutmeg, and salt—in a small bowl.
- To easily peel peaches, blanch them in boiling water for 1 minute, then pit and slice into ¼ inch thick pieces.
- In a large bowl, mix the sliced peaches with lemon juice and vanilla extract. Sprinkle the dry mixture over the peaches and gently stir to combine.
- Pour the filling into the chilled pie crust.
- Roll out the second dough piece for a lattice or full top crust. Place it over the filling, trim excess dough, and crimp the edges to seal.
- In a small bowl, whisk the egg and water to make the egg wash. Brush it generously over the crust.
- Bake the pie at 425°F for 20 minutes. Then place a foil-lined cookie sheet under the pie to catch drips, reduce oven temperature to 375°F, and bake for an additional 30–40 minutes (about 35 minutes), or until the filling is bubbling. If the crust browns too quickly, loosely cover with foil.
- Cool the pie for at least 2 hours before slicing to allow the filling to thicken. Cutting too soon may cause the filling to be too runny.