01 - Preheat the oven to 400°F. Line a baking sheet with parchment paper and set aside.
02 - In a mixing bowl, gently toss the sliced pears with granulated sugar, lemon juice, and ground cinnamon until evenly coated. Set aside to macerate.
03 - On a lightly floured surface, roll out the puff pastry sheet to smooth any seams. Using a knife or pastry cutter, divide into 6 equal rectangles.
04 - Arrange several pear slices in the center of each pastry rectangle, leaving a 1/2-inch border around the edges.
05 - Fold the edges of each pastry rectangle slightly inward over the pears to form a raised rim, pressing gently to secure the shape.
06 - Brush the exposed pastry edges generously with the beaten egg to ensure a rich golden finish during baking.
07 - Transfer the assembled pastries to the prepared baking sheet. Bake for 20 to 25 minutes until the pastry is puffed and deeply golden and the pears are fork-tender.
08 - While the pastries bake, combine the apricot jam and water in a small saucepan over low heat. Stir until the mixture becomes fluid and smooth. Strain through a fine-mesh sieve if a clearer glaze is desired.
09 - Remove the pastries from the oven. While still warm, brush the pear tops generously with the apricot glaze. Allow to cool slightly before serving. Best enjoyed warm or at room temperature.