Step 1: Preheat Oven : Preheat oven to 400°F (200°C) and line a baking sheet with parchment paper.

Step 2: Prepare Puff Pastry : Roll out the puff pastry sheet on a lightly floured surface. Cut the sheet into 12 equal rectangles, one for each mini hot dog.

Step 3: Assemble : Place a mini hot dog on each rectangle. Optionally, spread a small amount of mustard or ketchup on the pastry before adding the hot dog. Fold the pastry over the hot dog and pinch the edges to seal.

Step 4: Add Egg Wash : Brush the tops of the pastry with the beaten egg. Sprinkle with sesame seeds or poppy seeds if desired.

Step 5: Bake : Place the wrapped hot dogs on the prepared baking sheet. Bake for 18-20 minutes, or until the puff pastry is golden brown and puffed.

Step 6: Serve : Allow to cool slightly, then serve warm.