01 - Preheat oven to 400°F. Line a baking sheet with parchment paper.
02 - Unfold the thawed puff pastry sheet on a lightly floured work surface. Roll gently to smooth any creases if necessary.
03 - Spread raspberry preserves evenly across the pastry surface, maintaining a 1/2-inch border along all edges. Distribute fresh raspberries over the preserves if using.
04 - Starting from one long edge, roll the pastry tightly into a cylinder. Press gently to seal the seam.
05 - Using a sharp knife, cut the log into 8 equal slices, approximately 1 inch thick.
06 - Place the pastry slices cut-side up on the prepared baking sheet, spacing them 2 inches apart to allow for expansion during baking.
07 - Brush the tops of each roll lightly with beaten egg using a pastry brush.
08 - Bake for 18 to 20 minutes until the pastry is deeply golden and puffed. The layers should be visibly separated and crisp.
09 - Let the rolls cool on the baking sheet for 5 minutes. Dust generously with powdered sugar using a fine-mesh sieve before serving warm.