Thaw the puff pastry. Prepare an oven sheet pan by lining it with parchment paper then sprinkle it with half the brown sugar

Place the puff pastry plates next to each other on the pan. Prepare to join them by first roughen up the edges with a fork then add just a little water. Join the edges in a 1 cm overlap then press them together with the fork.

Roll out the dough so that all joints are smooth and the puff pastry is slightly thinner

Slice the apples as thin as you can

Mix all the other ingredients (except the egg) then add the apple slices

Spread the filling on half the puff pastry before folding in the edges. Then roll it to one long strudel and finish by brushing it with the egg

Bake in the oven at 225°C (437°F) for 15-20 min

Let it cool and store it wrapped in the fridge. It is best when served fridge cold