In a large mixing bowl, combine flour, salt, and granulated sugar. Cut in cold butter until the mixture resembles coarse crumbs. Gradually add ice water, mixing until the dough just comes together. Shape the dough into a disc, wrap in plastic, and refrigerate for at least 30 minutes.

Preheat your oven to 400°F (200°C). Rinse and slice fresh strawberries, placing them in a bowl. Add brown sugar, cornstarch, and lemon juice. Toss gently and let sit for about 10 minutes.

Roll dough into a rough 12-inch circle on a floured surface. Transfer to a parchment-lined baking sheet, leaving center clear for filling.

Spoon strawberry mixture onto the center of the dough, leaving a 2-inch border. Fold edges of dough over strawberries and brush exposed crust with egg wash. Sprinkle coarse sugar on top.

Bake for 35-40 minutes, until the crust is golden brown and strawberries are bubbling. Turn tray halfway through baking.

Let cool for at least 15 minutes before slicing. Serve warm or at room temperature, ideally topped with whipped cream or vanilla ice cream.