Thaw puff pastry until pliable but still cold. Preheat oven to 400°F (200°C) and line baking sheets with parchment paper.

Lightly roll each sheet to about 10×12 inches. Cut star shapes using a 2.5-inch cookie cutter. Gather scraps, re-roll once, and cut additional stars. You need an even number of stars.

Place half the stars on prepared baking sheets. Spoon ½–1 tsp fruit preserve into the center of each. Top with remaining stars, aligning edges.

Seal edges by pressing with a fork. Whisk egg with 1 tbsp water, then brush tops of pastries with egg wash.

Bake for 12–15 minutes, or until golden brown and puffed. Cool 5–10 minutes on sheet, then transfer to a rack.

Dust cooled pastries generously with confectioners’ sugar before serving.