Prepare the pastry

• Preheat the oven to 210 °C.
• Unroll the puff pastry and cut it into triangles.

Fill and roll

• Spread a spoonful of Nutella on the wide end of each triangle.
• Roll each triangle up from the wide end towards the tip to form a croissant.

Brush with egg wash

• Place the croissants on a baking tray lined with baking paper.
• Brush the tops with the beaten egg.

Bake

• Bake at 210 °C for 15 minutes, keeping an eye on them so they don't burn.
• Let cool slightly before serving.