1. In a food processor, combine the flour and salt. Add the chilled butter and pulse until the mixture resembles coarse crumbs.

2. Add the ice water and pulse until the dough just begins to come together. Do not overmix.

3. Turn the dough out onto a lightly floured surface and shape into a disc. Wrap in plastic and refrigerate for at least 30 minutes.

4. In a medium bowl, mix the diced apples, granulated sugar, cinnamon, and cornstarch until well combined.

5. Roll the dough out to 1/8-inch thickness on a lightly floured surface. Use a 4-inch round cookie cutter to cut out circles.

6. Place a heaping tablespoon of the apple mixture in the center of each dough circle. Brush the edges with the beaten egg and fold the dough over to create a half-moon shape, pressing the edges to seal.

7. Use a fork to crimp the edges and create a decorative pattern. Transfer the hand pies to a parchment-lined baking sheet.

8. Brush the top of each hand pie with the remaining beaten egg and sprinkle with coarse sugar.

9. Bake at 375°F for 20-25 minutes, or until the crust is golden brown.

10. Allow the hand pies to cool for 5 minutes before serving.