2refrigerated pie crustspurchased, or two homemade pie crusts
Preheat oven to 425 degrees.
Add the blueberries, cornstarch, lemon zest, lemon juice, sugar, vanilla extract, and salt to a medium-size bowl and stir to combine. Set aside.
Sprinkle the flour evenly on a cutting board and roll out the pie crusts. Use a 4-1/2 inch cutter and cut out 3 circles from each crust or 6 circles total.
Place the pastry circles on a baking sheet covered with parchment paper or a silicone non-stick baking mat.
Spoon 1-2 heaping tablespoon(s) of the blueberry mixture into the center of each pastry circle.
Gently fold over the edges of the pastry and crimp them gently, otherwise, they will unfold while baking and you will end up with a blueberry mess.
Whisk the egg and 1 Tbsp of water together. Use a pastry brush and brush the egg wash around the edge of each pastry. Sprinkle the pastry crusts with a small amount of sugar and bake until they are golden brown and the filling is bubbly, which should take approximately 15-20 minutes.
Remove from the oven and let cool. Serve warm or at room temperature.
You can substitute other fruit for the blueberries. Try cherries, strawberries, raspberries or blackberries. You can also make one delicious pie instead of the hand pies. To do this, place the pie crust in a pie tin and fill it with the blueberry filling. Add about 10 minutes to the baking time.