Make the dough. In a bowl, whisk flour, sugar, and salt. Cut in cold butter with a pastry cutter or your fingertips until pea-sized crumbs form. Drizzle in ice water, tossing gently, until the dough holds when pressed.

Chill the dough. Divide dough into two discs, wrap tightly, and chill 1 hour. Cold dough bakes flakier and is easier to roll.

Prep the filling. In a bowl, combine peaches, granulated sugar, brown sugar (if using), cornstarch, lemon juice, vanilla, cinnamon, and salt. Stir gently and let sit 10 minutes to start releasing juices.

Heat the oven. Preheat to 400°F (200°C). Line two baking sheets with parchment paper.

Roll out the dough. On a lightly floured surface, roll one disc to about 1/8 inch thick. Cut into 4- to 5-inch circles (or rectangles if you prefer). Gather scraps, chill briefly, and re-roll.

Fill the pies. Place dough rounds on the prepared sheets. Brush edges with a bit of egg wash. Spoon 1–2 tablespoons of peach filling into the center of each, leaving space at the edges.

Seal and crimp. Top with another dough round (or fold over if you cut rectangles). Press edges to seal, then crimp with a fork. Cut small slits on top for steam to escape.

Finish and chill. Brush tops with egg wash and sprinkle with coarse sugar. Chill the assembled pies in the fridge for 10–15 minutes to help them hold their shape.

Bake. Bake 18–24 minutes, rotating once, until golden brown and bubbly at the vents. If the edges brown too quickly, tent lightly with foil.

Cool and serve. Let pies cool on the sheet for 5 minutes, then transfer to a rack. Enjoy warm or at room temperature. They’re wonderful with a scoop of vanilla ice cream.