Instructions: 1. Prepare the Pie Crust: If using store-bought pie crusts, follow package instructions for rolling out and placing in a pie dish.
2. Preheat Oven: Preheat your oven to 375°F (190°C).
3. Prepare the Filling: In a large bowl, combine the sliced apples, granulated sugar, brown sugar, flour, cinnamon, nutmeg, salt, lemon juice, and chopped walnuts.
4. Assemble the Pie: Place one pie crust in the bottom of the pie dish. Pour the walnut apple filling into the crust, spreading it out evenly.
5. Bake: Place the pie in the preheated oven and bake for 45 to 50 minutes, or until the crust is golden brown and the filling is bubbling.
6. Cool and Serve: Allow the pie to cool for at least 30 minutes before slicing and serving. Serve warm with a scoop of vanilla ice cream or a dollop of whipped cream, if desired.