Preheat the oven to 425°F. Line a baking sheet with parchment paper or a silicone baking mat.

In a medium bowl, stir the frozen blueberries, sugar and corn starch together.

Roll out the chilled pie crust on a floured surface until it's about 1/8" thick. Cut 3 1/4 inch circles out.

In a small bowl, beat the egg and water together to make an egg wash.

Brush the egg wash lightly over half of the circles.

Scoop a heaping tablespoon of blueberries into the center the egg washed circles.

Gently and slightly stretch out the other circles. Using a fork, poke a few holes in the circle and place them on top of the blueberry topped circles. Press down the sides.

Place them on the baking sheet. Brush the pies with egg wash and sprinkle with turbinado sugar.

Bake for about 14-18 minutes or until golden brown. Serve warm.