Preheat oven to 425-degrees.

(For the sake of easy explanation, I am going to explain the top lattice strips in east and west, but you can also look at the pictures in the post or watch the video for a better view of making the lattice top).

Roll the bottom pie crust into a 9-inch glass or ceramic pie pan and poke small holes (with a fork) in the center and around the edge and set aside.

In a large bowl add the blueberries, sugar, cornstarch, ground cinnamon, salt, lemon zest, and lemon juice and mix well.

Pour the blueberry pie filling into the crust making sure the cornstarch is spread throughout.

Roll the top crust out on the counter and cut the crust into at least 10 strips.

Lay five of the pie dough strips over the top of the pie, spacing out each one (running east and west).

Fold back two east and west strips and lay a strip down the middle, going the opposite direction (north and south). Replace the two strips.

Fold back the other three strips (east and west) and place another strip on the pie going north and south and continue this until the pie has five pieces going in each direction.

Crimp off the ends of the pie strips and press against the edge of the crust.

Add the egg to a small bowl and beat. Brush the egg on top of the lattice crust. Optional: sprinkle some sugar on top of the lattice crust.

Place the pie on a cookie sheet, cover it with a pie shield, and bake for 15 minutes.

After 15 minutes, reduce the heat to 375-degrees and bake for 50-60 minutes, or until the blueberry juices are bubbling up through the lattice, or over the edge of the pie.

Let the pie set up at room temp for at least three hours.