01 - Preheat oven to 400°F. Line a baking sheet with parchment paper.
02 - Unfold 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, leaving a 1/2-inch border along all edges. Scatter fresh raspberries over preserves if using.
04 - Starting from one long edge, roll the pastry tightly into a compact cylinder. Press gently to seal the seam.
05 - Using a sharp knife, cut the roll into 8 equal slices, approximately 1-inch thick each.
06 - Place slices cut-side up on prepared baking sheet, spacing 2 inches apart. Brush tops generously with beaten egg.
07 - Bake for 18-20 minutes until rolls are deeply golden, puffed, and cooked through. Rotate pan halfway for even browning.
08 - Cool on baking sheet for 5 minutes. Transfer to wire rack and dust generously with powdered sugar. Serve warm.