Preheat the oven to 400°F. Line a baking sheet with parchment paper.
Lightly flour your work surface then unfold both sheets of puff pastry. Using a rolling pin, lightly roll each sheet to seal together any perforations.
Cut each sheet of puff pastry into a 9-inch circle. (The easiest way to do this is to trace around a large bowl.) Place one of the circles on the lined baking sheet.
Spread the Nutella in the center of the puff pastry circle on the baking sheet, leaving a 1/2-inch border around the edges of the circle.
Place the second puff pastry circle atop the Nutella, pressing the two pieces of puff pastry together lightly to seal them together.
Place a 2- or 3-inch glass or bowl in the center of the circle. Using a sharp knife or pizza wheel, cut from the edge of the glass outward to make 16 wedges around the circle.
Remove the glass then brush the pastry all over with the egg wash.
Twist two of the wedges in toward each other then pinch them together to seal them shut. Repeat the twisting and sealing process with the remaining wedges to form 8 points to the snowflake.
Sprinkle the sanding sugar (optional) all over the top of the snowflake then bake it until the pastry is golden brown and puffed, 20 to 25 minutes.
Remove the pastry snowflake from the oven and set it aside to cool slightly before dusting it with confectioners’ sugar and serving.
★ Did you make this recipe? Don't forget to give it a star rating below!