In a large bowl, whisk together the flour, sugar, and salt.

Cut in the cold butter using a pastry blender or your fingertips until the mixture resembles coarse crumbs with some pea-sized pieces of butter remaining.

Gradually add the ice water, 1 tablespoon at a time, mixing until the dough just comes together. Do not overmix.

Divide the dough in half, flatten each half into a disk, wrap in plastic wrap, and refrigerate for at least 30 minutes.

In a medium bowl, gently toss together the berries, sugar, cornstarch, and lemon zest.

On a lightly floured surface, roll out one disk of dough into a circle about 12 inches in diameter.

Using a 4-inch round cutter, cut out 3-4 circles from the dough. Re-roll scraps if necessary.

Place about 2 tablespoons of filling onto one half of each dough circle, leaving a 0.5-inch border.

Moisten the edges of the dough with water, then fold the other half over the filling to create a semi-circle. Crimp the edges with a fork to seal.

Repeat with the remaining dough and filling.

Preheat your air fryer to 375°F (190°C).

In a small bowl, whisk together the egg and water for the egg wash.

Brush the tops of the hand pies with the egg wash and cut a few slits in the top of each pie to allow steam to escape.

Place the hand pies in the air fryer basket in a single layer, working in batches if necessary. Do not overcrowd the basket.

Air fry for 8-12 minutes, or until golden brown and cooked through.

Let cool slightly before serving.