Use a food processor or a pastry cutter to prepare all-butter pie dough. See our buttery crust recipe with video here for step-by-step instructions. Take your disks of dough out of the fridge if you have already prepared your dough. Prep a clean work surface. Preheat oven to 350°F and position your oven rack in the center. Prepare a rimmed baking sheet to catch any drips during baking. You can place aluminum foil on the bottom of the baking sheet to catch drippings and make cleanup easy.
In a large bowl, prepare the blueberry pie filling by gently mixing together the blueberries, sugar, flour, corn starch, lemon juice, lemon zest, cinnamon, and salt. The blueberry mixture should be evenly coated.
Roll out half of the dough (one disk) on a lightly floured surface to a 13-inch circle. Transfer it to your buttered 9-inch glass pie plate (or pie pan) as the bottom crust.
Pour the blueberry filling into the shell and dot the top with the tablespoon of cold butter.
Roll out the second disk of dough with a rolling pin and use a sharp knife to cut lattice strips. Use these strips of dough to weave a lattice crust and trim any excess dough around the edges. For help with lattice pie crust, click here. Brush the edges of the dough and the lattice top with the egg wash (egg + water). Sprinkle generously with Turbinado sugar for that golden sparkle.
Place the filled pie on the baking sheet, transfer pie to the heated oven, and bake for 30 minutes on one side first.
Check the top for doneness: If the top has turned golden brown, tent it with aluminum foil to prevent burning or use a pie ring if the edges are turning dark. Then turn the baking sheet around and continue baking for another 30 minutes, or until the filling is bubbling and the crust is deeply golden. Remove from oven and cool on a wire rack or stovetop. Let it cool completely — this helps the filling firm up and not run. Cut, serve, and enjoy!
