FOR THE PIE CRUST

1. Make the pie dough and form it into 2 round discs. Refrigerate the discs while you make the filling. 

FOR THE FILLING

1. Drain any access juice from the thawed cherries, reserving 1/3 cup for the filling.  Add the cherries, reserved juice, sugar and cornstarch to a medium saucepan over medium heat. Stir constantly until the mixture comes to a boil and begins to thicken, about 5 minutes, and remove from the heat. Set aside.
2. Preheat an oven to 400 degrees.
3. Remove one disc at a time from the refrigerator. On a lightly floured surface, roll the dough out into a rough circle about 1/8-inch thick. Using a 4-inch heart cookie cutter, cut out 12 heart shaped pieces of dough, gathering up the scraps and re-rolling them as needed. Place the dough hearts on a cookie sheet, leaving plenty of space between them. 
4. Make the egg wash by whisking together the egg and water. Brush the edges or the entire heart with the egg wash. This will help the edges of the top piece of dough to adhere to the bottom edges.
5. Stop and repeat step #3 with the remaining disc of dough, except cut them and leave aside while you add the filling to the bottom hearts.
6. Spoon 1 tablespoon of the cherry filling on top of each of the 12 bottom hearts. Try to drain off most of the juice by lightly pressing the spoonful of cherries against the side of the pan.
7. Arrange the 12 remaining hearts on top of the cherries. Using your fingertips, press the edges of the top and bottom hearts together. Then take a fork and lightly fork the edges. Don’t worry if you see some juice escape. 
8. Brush some of the egg wash on the tops and sprinkle with coarse or sparkling sugar.
9. Bake for approximately 18 to 20 minutes or until lightly browned on top.
10. Serve warm with some ice cream on the side or at room temperature.