Use ready-to-roll refrigerated piecrusts to make this super easy & super yummy blueberry hand pie treat.
In a medium-sized saucepan, combine 1 1/2 cups blueberries, 1/4 cup sugar and the lemon juice. Cook over medium heat for about 5 minutes, stirring occasionally. Reduce heat to medium-low and cook 3 minutes, until all berries have burst.
Meanwhile, in a small bowl, stir the cornstarch and 2 tablespoons of water until smooth. Add the cornstarch slurry to the berries and cook for just 1 minute, until thickened. Remove from heat and stir in the remaining 1/2 cup of blueberries.
Place saucepan in a bowl of ice water. Stir mixture frequently, until cooled.
Preheat oven to 375°F.
Unroll 1 pie crust on a lightly floured work surface, then roll out to 1/16-inch thickness. Using a 4 1/2-inch round cutter, cut out 4 rounds.
Place 2 tablespoons of the blueberry filling on half of each round, leaving a 1/2-inch border. Dampen the edges with a fingertip dipped into water. Fold dough over filling, pressing the edges to seal. Crimp with the tines of a fork that has been dipped in flour. Refrigerate for 15 minutes. Repeat with remaining piecrust and filling.
Brush pies with the egg wash and make 2 slits in the center of each (for steam to escape). Sprinkle evenly with 1 tablespoon of sugar. Bake for 20 minutes, until golden. Let cool.
If desired, serve with a side of whipped cream or a scoop of vanilla ice cream.