01 - Preheat oven to 400°F. Line a baking sheet with parchment paper and set aside.
02 - In a mixing bowl, gently toss the peeled, cored, and sliced pears with granulated sugar, lemon juice, and ground cinnamon until evenly coated. Set aside to macerate briefly.
03 - On a lightly floured work surface, roll out the thawed puff pastry sheet to smooth out any seams. Using a knife or pastry cutter, divide the sheet into 6 even rectangles.
04 - Arrange several pear slices in the center of each pastry rectangle, leaving about a 1/2-inch border around the edges. Fold the edges of the pastry slightly inward over the pears to create a raised rim.
05 - Brush the exposed pastry edges generously with beaten egg to ensure a glossy, golden finish after baking.
06 - Transfer the assembled pastries to the prepared baking sheet. Bake for 20 to 25 minutes, until the pastry has puffed and turned golden brown and the pears are fork-tender.
07 - While the pastries bake, combine apricot jam and water in a small saucepan over low heat. Stir until the mixture becomes smooth and liquid. Strain through a fine-mesh sieve if a smoother glaze is desired.
08 - 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.