Blueberry Pie is a fantastic classic dessert for any time of the year. The combination of berries, warm spices, zest, and homemade flaky crust is divine!
In a medium mixing bowl, mix sugar, cornstarch, cinnamon, salt, and zest together. Set aside. Place grated apple in a towel or paper towel and ring out juice. In a large mixing bowl, combine blueberries, grated apple, and lemon juice. Set aside.
Roll out one round of pie dough and place in a 9 inch pie plate.
Mix the sugar mixture into the blueberries until coated. Pour the berries into the pie crust forming a mound (it will cook down).
Roll out the remaining pie dough and form top crust as desired- lattice, braid, whole (cut slits to vent).
In a small bowl, beat egg and water together. Lightly brush the top of pie with egg wash (you won't use all of it!) and then sprinkle with sugar (if desired).
Place pie on a rimmed baking sheet (to catch any drips) and bake for 15 minutes. Without opening the oven, lower the temperature to 375°F and cook 50-60 more minutes until golden. (Cover edges after first 30 minutes of cooking).