Preheat oven: Set to 375°F (190°C).
Prepare apples: In a large bowl, toss sliced apples with sugar, brown sugar, cinnamon, nutmeg, lemon juice, and flour.
Assemble the pie:
Roll out one pie crust into a pie pan.
Fill with the apple mixture and dot with small pieces of butter.
Cover with the second crust, seal edges, and cut slits on top to vent.
Brush with beaten egg for a golden finish, if desired.
Bake: 50–60 minutes, until the crust is golden and the filling is bubbly.
Cool and serve: Let the pie cool slightly before slicing.
