Prepare the Puff Pastry:

Preheat the oven to 400°F (200°C). Line a baking sheet with parchment paper.
Roll out the puff pastry on a lightly floured surface and cut it into 6 equal rectangles.
Assemble the Pockets:

Spread a thin layer of Dijon mustard or mayonnaise on one half of each rectangle (optional).
Add a layer of ham and sprinkle grated cheese on top. Season with black pepper if desired.
Fold the other half of the puff pastry rectangle over the filling to create a pocket.
Seal the edges by pressing with a fork, ensuring the filling stays inside.