1. Preheat your oven to 425°F (220°C).
2. In a mixing bowl, combine flour and salt for the crust. Cut in the cold butter until the mixture resembles coarse crumbs. Gradually add ice water, mixing until the dough comes together.
3. Divide the dough in half, shape into discs, wrap in plastic, and refrigerate for at least 30 minutes.
4. In another bowl, mix the sliced apples with both sugars, flour, lemon juice, and chai spices.
5. Roll out one disc of dough on a floured surface and fit it into your pie dish. Add the apple mixture.
6. Roll out the second disc of dough and place it over the apples. Trim and crimp the edges. Cut a few slits in the top crust to allow steam to escape.
7. Brush the top crust with the beaten egg.
8. Bake for 45-60 minutes, until the crust is golden and the filling is bubbly. If the edges brown too quickly, cover them with foil.
9. Let the pie cool before serving.