Mixed Berry Pie

In a large bowl, mix 360g all-purpose flour, 3/4 teaspoon fine sea salt, and 12g (1 tablespoon) granulated sugar. Add 226g cold cubed unsalted butter, and use your fingertips to rub butter into flour until the mixture forms pea-sized and almond-sized crumbs. Drizzle 60ml ice water over the mixture, tossing gently, adding up to 20ml more ice water 1 teaspoon at a time until the dough just holds together when squeezed. Split dough into two equal discs, wrap tightly in plastic wrap, and chill in the refrigerator for 1 full hour before rolling.

In a large mixing bowl, combine 700g prepared mixed berries, 125g (1/2 cup plus 2 tablespoons) granulated sugar, 45g cornstarch, 1 tablespoon lemon juice, 1 teaspoon lemon zest, and 1/4 teaspoon fine sea salt. Toss gently until all berries are evenly coated in the sugar-cornstarch mixture, then set aside for 15 minutes at room temperature to let the berries release their natural juices.

Once dough is chilled, lightly flour a clean work surface. Roll one dough disc out to a 30cm (12-inch) circle, about 3mm (1/8-inch) thick. Carefully lift the dough and drape it over a 23cm (9-inch) standard ceramic pie dish, pressing it gently into the bottom and up the sides of the dish. Trim any overhanging dough to a 2.5cm (1-inch) border around the dish edge, then place the dish back in the refrigerator to chill for 10 minutes while you preheat the oven.

Remove the chilled bottom crust from the fridge, and pour the rested berry filling and all accumulated juices evenly into the crust. Roll the second dough disc out to an identical 30cm (12-inch), 3mm thick circle. Drape the top crust over the filling, then trim the top crust overhang to match the bottom crust’s 1-inch border. Fold the two crust edges together, pressing firmly to seal, then crimp the edge decoratively with your fingers or a fork. Cut 4 small 2cm slits in the top crust to allow steam to escape during baking.

Preheat your oven to 200°C (400°F). Brush the entire top crust and crimped edge with the beaten egg, and sprinkle with the remaining 13g (1 tablespoon) granulated sugar. Place the pie on a rimmed metal baking sheet (to catch bubbling juices) and bake on the middle oven rack for 25 minutes, then reduce the oven temperature to 190°C (375°F) and bake for an additional 30-35 minutes, until the crust is deep golden brown and the filling is visibly bubbling thickly through the steam slits.

Once baked, transfer the pie to a wire cooling rack to cool completely at room temperature for a minimum of 3 hours (or up to overnight, loosely covered) before slicing. This resting time allows the cornstarch-thickened filling to set fully, preventing runny slices. Serve at room temperature or slightly warmed, with a dollop of whipped cream or vanilla ice cream if desired.