Preheat the oven to 350 degrees Fahrenheit.
Roll both of the pie crusts out on a lightly floured counter top.
Cut 2.5 inch circles into the pie crust with a round cookie cutter, or top of a cup, jar, etc.
Place each circle into the opening of a greased mini muffin pan. Press down into the bottom of the pan.
In a medium bowl, combine the berries, granulated sugar, cornstarch, and lemon zest.
Scoop about 1 TBS of the berry mixture into each pie crust, filling them evenly.
Cut thin 1/2 centimeter strips with the remaining pie crust. Use a few pieces to form a mini lattice crust over the top of each pie. Pressing the edges into the pie crust base.
In a small bowl combine the egg and water to make an egg wash. Brush over the top of each pie with a silicone brush.
Sprinkle the tops with coarse sugar.
Bake the mini pies for about 20-25 minutes, until the crust is golden brown, and the berries are bubbling.
Let the pies cool for about 5 to 10 minutes in the pan, then transfer them carefully to a cooling rack to cool to room temperature, and serve.