Preheat oven to 375 degrees.
Line a baking sheet with parchment paper, and set aside.
In a large bowl, combine blueberries, lemon juice, lemon zest, basil, sugar, and cornstarch.
Roll out pie dough, and cut into 5" circles.
Place prepared dough on baking sheet.
Spoon blueberry mixture onto one half of each circle.
Fold over other half, and crimp edges with a fork.
Slice the top of each pie to allow the steam to escape.
Brush each pie with egg or milk mixture, and bake 15-20 minutes, or until golden brown.
Let cool 10 minutes before serving.