Preheat:

 

Set your oven to 450°F (232°C).

Prepare the Crumble Topping:

 

In a bowl, mix flour, brown sugar, granulated sugar, and cinnamon.

Add the chilled butter and use a fork (or your hands) to combine until crumbly.

Set aside.

 

Make the Filling:

 

Peel, core, and slice the apples thinly (about 1/8-inch slices).

Toss the slices with sugar, flour, lemon juice, zest (if using), cinnamon, and nutmeg until evenly coated.

Assemble the Pie:

 

Arrange the apple slices in the prepared pie crust, piling them high as they will shrink while baking.

 

Pour any remaining juice over the apples.

Evenly spread the crumble topping over the apples and gently press it down.

Place the pie dish on a baking sheet to catch any drips.

Bake the Pie:

 

Bake at 450°F (232°C) for 15 minutes.

Reduce the oven temperature to 350°F (177°C) and continue baking for 45–55 minutes, or until the apples are tender when tested with a knife or skewer.

Cool and Serve:

Let the pie cool slightly before serving. Enjoy it warm or at room temperature.

 
Tips

If the topping looks too dry, keep mixing it until it forms clumps. You can use your hands for better results.

To prevent the topping from over-browning, cover the pie with foil if needed.

Granny Smith apples are ideal for their tartness and ability to hold their shape during baking.