In a food processor, pulse the flour, sugar, and salt. Add cold cubed butter and shortening, pulsing until the mixture resembles coarse crumbs. Slowly add ice water, pulsing until the dough begins to come together.
Turn the dough into plastic wrap, shape into a disk, then refrigerate for at least 30 minutes.
In a large bowl, gently combine blueberries, sugar, cornstarch, lemon juice, lemon zest, cinnamon, and salt.
Divide the chilled dough into 6 equal portions. Roll each into a 7-8″ circle on a lightly floured surface.
Transfer the dough rounds to a parchment-lined baking sheet. Spoon about ¼ cup of blueberry pie filling into the center, leaving a 1″ border. Fold the edges over, pleating as needed.
Brush the dough with egg wash, then sprinkle with Turbinado sugar. Bake at 425°F for 16-18 minutes, until golden brown and bubbly Cool slightly, then top with ice cream or whipped cream. Enjoy!