Instructions

1. Roll out 1 pie crust into a 12-inch round if needed. Transfer it to a 9-inch standard pie pan (not deep dish). Press the dough into the bottom and up the sides of the pie plate. Roll out the second pie dough onto a sheet of parchment paper into an 11-inch round if needed. Slide onto a baking sheet. Refrigerate both pie doughs while the oven heats.
2. Line a baking sheet with aluminum foil or parchment paper. Place on the middle rack of the oven and heat the oven to 425°F. Whisk 1 large egg and 1 tablespoon water together in a small bowl with a fork.
3. Stir 30 ounces fresh blueberries, 1 cup granulated sugar, 1/4 cup cornstarch, the finely grated zest of 1 medium lemon, 2 tablespoons lemon juice, and 1/2 teaspoon kosher salt together in a large bowl, doing your best break up any clumps of sugar or cornstarch with your fingers.
4. Brush the pie dough in the pie pan with a thin layer of the egg wash (save the remaining for brushing the top crust). Scrape the blueberry filling into the pie pan and arrange into an even layer; make sure any loose sugar is distributed evenly over the blueberries.
5. Cut the pie dough on the parchment into 1-inch wide strips. Transfer every other strip to the top of the pie, spacing them evenly. Create a lattice pattern by alternating and folding in the remaining strips (here's a step-by-step tutorial). Crimp the edges to seal. Brush the lattice crust and edges of the pie dough with the egg wash.
6. Place the pie on the hot baking sheet and bake for 15 minutes. Reduce the oven temperature to 375°F. Bake until the juices in the center are vigorously bubbling and register at least 203ºF, and the crust is golden brown, 45 to 50 minutes more. Let cool for at least 3 hours so the filling can set up before slicing and serving.