Start by mixing sugar, salt and cornstarch in a small mixing bowl then set aside.
Place cherries in a small saucepan over medium heat. When the cherries start to bubble and release their juices, stir in the sugar, salt and cornstarch mixture. NOTE: When working with fresh fruit, the amount of thickener you need depends on how ripe the fruit is. If you’re using super sweet, ripe fruit, increase the cornstarch by 1 or 2 Tbsp.
Stir the cherries vigorously until the sugar has dissolved and the filling has thickened. Then reduce the heat to low and cook for about two more minutes. If the filling seems too thick, simply add a splash of water to thin it out.
Remove the saucepan from heat. Stir in lemon juice then let cool completely. Meanwhile, preheat the oven to 375 degrees.
Unroll refrigerated pie crust onto a lightly floured surface. Then cut seven rounds from each pie crust using a 3″ round pastry cutter—you should have 14 rounds when finished.
Place approximately 2 tbsp cherry pie filling in the center of seven of the pie crust rounds, leaving a half-inch border around the edges. Then place the remaining pie rounds on top of each filled round, pressing along the edges to seal then crimping with your fingers or the tines of a fork for a decorative effect! Then cut two to three small vent holes on the top of each pie. This will allow steam to escape while they’re cooking.
Place pies on a baking sheet lined with parchment paper and brush each pie with egg wash. Sprinkle generously with granulated sugar and bake for 14-16 minutes, or until golden brown along the edges.