Preheat the oven to 400°F (200°C).

On a floured surface, roll out one pie crust into a 14-inch (35 cm) circle (about ⅛-inch (3 mm) thick) and line a 9-inch pie tin with it. Leave a 1-inch (2 ½ cm) overhang and trim away the rest.

In a large mixing bowl, combine the strawberries, grated apple, sugar, cornstarch, lemon juice, vanilla, and salt, and then pour into the pie crust.

Roll out the second pie crust into a 14-inch (35 cm) circle (about ⅛-inch (3 mm) thick) and cut it into 10 (1 ½-inch/3 ½ cm) wide strips.

Lay 5 strips in one direction across the pie and then lay the other 5 strips in the opposite direction to create a lattice effect. Leave a 1-inch (2 ½ cm) overhang for the lattice strips and trim away the excess. Press the strips into the bottom crust to seal, then fold the bottom crust overhang up and over the top edge to create a nice, thick border. Crimp with your fingers or a fork.

Brush the crust with the egg wash and sprinkle with a little sugar.

Place the pie on a baking sheet to catch any drippings and bake for 20 minutes.

Reduce the temperature to 350°F (180°C) and continue baking until the juices are bubbling thickly and the crust is golden brown, about 45 minutes.

Let cool for at least 6 hours before serving for it to be sliceable. Serve with whipped cream or vanilla ice cream. Store leftovers, loosely covered and at room temperature for up to 2 days.