In a large bowl, whisk together flour, 1 tsp sugar, and 1 tsp salt. Add the cold butter cubes and cut them into the flour mixture using a pastry blender, two knives, or your fingertips, until the mixture resembles coarse crumbs with some pea-sized pieces of butter remaining.

Gradually add the ice water, 1 tablespoon at a time, mixing lightly with a fork until the dough just comes together. Be careful not to overmix. If the dough is too dry, add a tiny bit more water, 1 teaspoon at a time.

Divide the dough in half. Form each half into a flat disk, wrap tightly in plastic wrap, and refrigerate for at least 30 minutes (or up to 2 days).

In a large bowl, combine the pitted cherries (if using frozen, do not thaw), 1 cup granulated sugar, cornstarch, lemon juice, almond extract (if using), and 1/4 tsp salt. Stir gently to combine.

Pour the cherry mixture into a medium saucepan. Cook over medium heat, stirring frequently, until the mixture thickens and comes to a gentle boil, about 8-12 minutes. The cornstarch needs to activate, so make sure it thickens significantly. Remove from heat and stir in the small pieces of butter until melted. Set aside to cool slightly while you prepare the crust.

Preheat your oven to 425°F (220°C).

On a lightly floured surface or between two sheets of parchment paper, roll out one disk of pie dough into a 12-inch circle. Carefully transfer the dough to a 9-inch pie plate. Trim the edges, leaving about a 1/2-inch overhang.

Pour the slightly cooled cherry filling into the pie crust. Distribute evenly.

Roll out the second disk of pie dough. You can either place it directly over the filling (cutting a few slits in the top for steam) or cut it into strips for a lattice top. Carefully place the top crust over the filling.

Trim the edges of the top crust, leaving a 1/2-inch overhang. Fold the overhangs of both crusts under and crimp the edges together using your fingers or a fork to seal.

In a small bowl, whisk together the egg and water to make an egg wash. Brush the top crust generously with the egg wash, then sprinkle evenly with 1 tbsp granulated sugar.

Place the pie on a baking sheet (to catch any potential drips). Bake at 425°F (220°C) for 15 minutes. Then, reduce the oven temperature to 375°F (190°C) and continue baking for another 45-50 minutes, or until the crust is golden brown and the filling is bubbly and thick. If the crust starts to brown too quickly, loosely cover the edges with aluminum foil.

Remove the pie from the oven and let it cool completely on a wire rack for at least 3-4 hours before slicing and serving. This allows the filling to set properly.