Turnovers

Preheat oven to 350°.

Toss blueberries, blackberries, sugar, ginger, lime juice, salt, and 2 Tbsp. flour in a medium bowl to combine.

Beat egg and heavy cream in a small bowl until no streaks remain.

Roll out pie dough on a lightly floured work surface to a 15x10" rectangle. Cut a thin border around dough to square off edges. Cut dough in half lengthwise and then in thirds crosswise to form six 5" squares.

With a Pastry Brush, brush edges with egg mixture, then mound about ¼ cup blueberry filling in middle  each square.

Working with 1 square at a time, fold corner opposite filling up and over to create a triangle; press edges with a fork to seal.

Place on a parchment-lined baking sheet and brush with remaining egg mixture.

Cut about a 1"-long slit in the center of each turnover.

Bake until pastry is golden brown and juices run from slits, 35–45 minutes.

Let cool on baking sheet until slightly warm.

Glaze and Assembly

Whisk powdered sugar, vanilla, and salt in large wide bowl. Whisking constantly, add warm water a tablespoonful at a time until glaze is thick and smooth and falls off the whisk in a slowly dissolving ribbon (it should look like sweetened condensed milk).

Working one at a time, dip top sides of slightly warm turnovers into glaze, letting excess drip back into bowl.

Transfer to a wire rack (set on parchment paper to collect drips) and let sit until turnovers are cool and glaze is set, about 30 minutes.