Peel the bananas and cut each one in half crosswise to create smaller portions that are easier to work with.
Using a paring knife, make a shallow slit lengthwise down the center of each banana half. Be careful not to cut all the way through — this will create a small pocket for the filling.
Fill the center of each banana with a spoonful of hazelnut cream, spreading it gently into the slit. Avoid overfilling to prevent the cream from leaking during baking.
Step 3: Assemble and Bake
Wrap each banana half with a puff pastry strip, slightly overlapping the edges to ensure the banana is completely covered. The spiral wrapping will give a beautiful appearance and a satisfying crunch once baked.
Place the wrapped bananas on the prepared baking sheet, seam-side down, leaving a little space between each roll.
In a small bowl, beat one egg to make an egg wash. Brush the tops of the banana rolls evenly with the egg wash to create a glossy golden finish.
Sprinkle a light dusting of sugar over the tops to add sweetness and a caramelized touch once baked.
Bake in the preheated oven for 25 minutes, or until the pastry is puffed and golden brown. The bananas will soften, and the hazelnut cream will become luxuriously melted inside.
