Preheat oven to 375°F (190°C).
Roll out bottom pie crust and place it in a 9-inch pie dish.
In a large bowl, mix apples, granulated sugar, brown sugar, flour, cinnamon, nutmeg, lemon juice, and salt.
Spoon apple mixture evenly into the pie crust.
Drizzle half of the salted caramel sauce over the apples.
Dot with small cubes of butter.
Cover with top crust and seal edges, then cut small slits for steam.
Brush crust with beaten egg.
Bake for 50–55 minutes until crust is golden and filling is bubbly.
Let pie cool for at least 1 hour before slicing.
Drizzle remaining salted caramel sauce over slices before serving.
