Preheat your oven to 375 degrees F.
Make the recipe for pie dough and divide it into two even-sized balls. You can also use pre-made frozen pie dough. You will need two dough circles. Let the frozen dough thaw before using.
Roll one of the pie crust doughs into a 13” round circle and lay it into a deep, 9” pie pan. Press the dough into the sides of the pan.
In a large mixing bowl, toss the blueberries, lemon zest, lemon juice, vanilla, flour, and sugar together, coating all the blueberries in the dry ingredients.
Pour the blueberry mix into the pie pan.
Roll the second pie crust into a ten-inch circle and then cut it into ten one-inch strips.
Use the pie dough strips to make a lattice top. Place five strips of dough vertically across the pie, spacing them about an inch apart. Fold every other strip back and then lay a pie dough strip horizontally across the pie, going over half of the vertical strips. Put the pulled-back strips down over the horizontal strip. Then, pull back the alternate strips and lay a second pie dough strip horizontally. Continue adding alternating strips, creating a lattice pattern across the top of the pie.
Pinch the edges of the pie, sealing the lattice strips to the bottom pie crust.
Whisk the egg and water in a small bowl, then brush the egg wash over the pie dough strips using a pastry brush.
Bake the pie for 45 minutes. The crust will be golden brown and the pie will be bubbling around the edges.
Let the pie cool before slicing and serving.