In a mixing bowl, combine the flour, salt, and sugar, stirring briefly to combine.

Add the cold, cubed butter and blend until it resembles coarse crumbs.

Add the ice water gradually and mix until the dough forms but remains slightly crumbly.

Form the dough into a disk, wrap in plastic wrap, and chill in the refrigerator for at least 30 minutes.

In a mixing bowl, combine the blueberries, sugar, cornstarch, and lemon juice. Toss to coat.

Preheat your oven to 400°F and line a baking sheet with parchment paper.

Roll out the chilled dough to about 1/8 inch thickness on a floured surface.

Cut out circles (approximately 4 inches in diameter) from the rolled dough.

Place a tablespoon of blueberry filling in the center of each circle, leaving a ¼-inch border.

Fold the dough over to create a half-moon shape and seal the edges with a fork.

Brush the tops with beaten egg and make small slits for steam to escape.

Bake in the preheated oven for 20-25 minutes until golden brown.

Whisk together the powdered sugar and lemon juice until smooth. Adjust consistency as needed.

Drizzle the icing over the cooled hand pies and allow to set before serving.