Preheat oven to 400° F / 205° C. Line a rimmed half-sheet baking tray with parchment, and set aside until ready to use.

In a medium bowl, add diced peaches, brown sugar, cornflour, cinnamon, cardamom, vanilla bean paste, and salt, and stir until dry ingredients are fully incorporated. Stir in lemon juice and zest. Set aside.

On a silicone rolling mat or lightly floured countertop, unroll one sheet of shortcrust pastry. With a 3.75-inch* round cutter, cut the pastry into discs. Repeat with the second sheet of pastry, then use a rolling pin to re-roll the scraps and cut the remaining discs. When finished, you should have 20 discs total.

Arrange half of the discs on the prepared tray.

Add the blueberries and walnuts to the peach mixture, and stir until nicely incorporated.

Spoon the peach, blueberry, and walnut mixture on top of the discs, allowing a half-inch border around the outside edge. Use all of the mixture, dividing it equally between the ten discs.

With a pastry brush, lightly brush beaten egg around the edges of each disc.

Top each disc with a second disc of pastry, then use your fingers to gently seal the edges.

With a pastry brush, brush the tops of the discs with beaten egg.

Use a fork to crimp the edges of each disc.

With a sharp knife, score the tops of the pies. (Alternately, you can use a fork to gently pierce each pastry 3-4 times.)

Sprinkle each pie with a generous helping of Demerara sugar.

Bake in preheated oven for 25 minutes, or until pies are golden brown with fruit bubbling from the tops of the pastries.

Allow hand pies to cool on the tray** for five minutes, then transfer to a wire rack to cool completely.

Peach, blueberry, and walnut hand pies are best enjoyed on the day they are made, and ideally while still slightly warm. Store leftovers in an airtight container at room temperature for up to three days.