For the onion sticks, mix onion soup powder with crème fraîche. Roll out the first puff pastry. Spread the onion soup-cream fraich mixture on it. Place the second puff pastry on top and press down lightly. Cut strips approx. 1.5-2 cm wide.
Turn the strips and place them on a baking tray. Preheat oven to 200 °C hot air with a heatproof container filled with plenty of water. Steam will improve the “flaking”.
Brush the Stangerl with beaten egg and bake for about 15 minutes until golden brown.