Homemade Blueberry Pop Tarts

MAKE AHEAD

1. Prepare the two pie doughs, form into two discs, wrap with plastic wrap, and keep in the refrigerator for up to 3 days.

PREPARE THE BLUEBERRY POP TARTS

1. Heat a medium-sized saucepan over medium heat and add 1½ cups of the blueberries, sugar (¼ cup), and lemon juice (1 tbsp). Stir with a wooden spoon until berries begin to release their juices and break down, about 5 minutes.
2. Meanwhile, in a small bowl, stir together the cornstarch and 2 tablespoons water. Add the cornstarch slurry to the saucepan and stir until thickened, a couple of minutes longer. Remove from heat and stir in the remaining ¼ cup of blueberries. Transfer to a bowl and set aside.
3. Preheat the oven to 375°F.
4. Working with one disc of dough at a time, transfer to a liberally floured work surface. Use the palm of your hand to begin flattening the dough. Use a floured rolling pin to gently roll the dough to a rough 10"x12" shape. Use a cookie cutter, or sharp knife, to cut the edges off each side of the dough to make a clean 10"x12" rectangle.
5. Using your pizza cutter, or knife, divide the dough into 3 rectangles, each 4"x 10."
6. Place about 2 to 3 tablespoons of the blueberry filling on one half of a rectangle, leaving a ½-inch border on each side. Brush a little water along the edges of each pie, and then use your fingers to carefully fold the side of the dough without the filling over the side with the filling.
7. Brush each pie with the egg wash. Then, use a small knife to cut a couple of slits on the top of each pie creating an "X." Sprinkle with a little sugar over the top of each pop tart and then transfer them carefully with a spatula to a baking sheet.
8. Bake the pies until golden, about 25 minutes (rotate the baking sheet halfway through).
9. Let the pies cool on the pan on a wire rack.
10. Meanwhile, mix 1¼ cup confectioners' sugar into a bowl with 2 tablespoons of water. The mixture should have the consistency of heavy cream.
11. Brush the icing over the cooled pies. Serve warm or at room temperature.