In a large bowl, mix the flour, sugar, baking powder, and salt until evenly combined.

Add the grated frozen butter. Using your fingertips, gently rub the butter into the flour, leaving some small pieces of butter throughout the mixture. These little pieces help create flaky layers as the pies bake. Try not to overwork the dough because you don't want the butter to melt.

Add the cold cream and water. Use a fork to mix until a shaggy dough forms. If the dough seems too dry, add cold water 1 teaspoon at a time until it mostly holds together.

Bring the dough together with your hands and shape it into a rectangle. Wrap it in plastic wrap and refrigerate for at least 30 minutes.

Slice the strawberries and add them to a medium pot with the sugar, cornstarch, and lemon juice.

Cook over medium-low heat, stirring regularly, until the strawberries soften and the mixture thickens. This should take about 5–7 minutes.

Remove from the heat and let the filling cool completely before assembling the pies.

Line baking sheets with parchment paper. Whisk the egg with 2 teaspoons (10ml) of water to make the egg wash.

Divide the chilled dough into two portions and work with one portion at a time. Roll the dough between two lightly floured sheets of parchment until it is about ¼-inch (6mm) thick.

Cut the dough into 3–3 ½-inch (7.5–8.5cm) rounds. You can use a fluted cutter if you want decorative edges. Try to cut as many rounds as possible from the first roll. You can reroll the scraps, but working the dough too many times can make the crust less flaky.

Place half of the dough rounds on the prepared baking sheet. Add about 2 tablespoons (30g) of strawberry filling to the center of each round.

Brush a little egg wash around the edges of the dough. Place another dough round on top and gently press around the filling to seal the edges. You can also use a fork to press around the edges for an extra seal.

Brush the tops with egg wash and sprinkle with raw cane sugar. Use a sharp knife to make a small vent in the top of each pie.

Place the assembled pies in the refrigerator for 15 minutes.

Preheat the oven to 375°F (190°C) about 10 minutes before baking.

Bake for 27–30 minutes, or until the edges are golden brown.

Let the hand pies cool completely before serving.