¾cupgranulated sugar, divided, plus more for sprinkling
2tablespoonscornstarch(also known as "cornflour" in the UK)
24ouncesButtery Flaky Pastry Dough (the amount you would use for a double-crust pie)
1cuplukewarm water
Instructions
Place cherries and ½ cup of the sugar into a large heavy saucepan. Bring to a simmer over medium heat and cook for 5 minutes, stirring frequently. Remove the cherries with a slotted spoon to a bowl, leaving the juices in the pan. Press the cherries in the bowl with the back of a large spoon or spatula to press out more juice and add the juice to the pan.
Whisk together 2 tablespoons cornstarch with 2 tablespoons water. Add this slurry to the cherry juice in the pan and simmer the juice over medium heat for about 3-4 minutes, until it has really thickened.
Mix the cherries back into the thickened juice. Cool the cherry mixture down to room temperature (I did this by placing a pie plate of ice cubes under the pan, and sticking the whole thing outside in the cold air. The fridge will work if it's not cold out where you are!) Set aside.
Slice each wrapped disk of pastry dough into 8 portions, 16 total.
Roll out one portion into an 8" circle. Into the center of one circle, place a heaping tablespoon of cherry pie filling. Dip a finger into the ice water and wet the edge of the dough circle. Place another dough circle on top. Press the edges together. Wet the top edge of the dough and then fold the edges up and over all around to make a seam. Place the pie on a parchment-lined baking sheet.
Use a fork dipped in flour to crimp the edge. Repeat with the remaining dough portions and cherry filling, to make a total of 8 pies. Place the baking sheet with the pies into the fridge 30 minutes.
Preheat the oven to 400° F. Lower one oven rack to the position just below middle.
In a small dish, combine the lukewarm water with the ¼ c. of granulated sugar – stir until the sugar is dissolved.
Remove the baking sheet from the freezer. Use a paring knife to cut 1 or 2 vents into the tops of the pies. Use a pastry brush to brush each pie with the sugar-water and then sprinkle granulated sugar liberally over the tops.
Bake the pies for 30 minutes until the tops are brown and the pies are puffed. Move the pies to a cooling rack and cool for at least 15 minutes.