01 -
Set the oven to 400°F (200°C) and line a baking sheet with parchment paper to prevent sticking.
02 -
On a lightly floured surface, roll out thawed puff pastry sheets to smooth creases and slightly enlarge them. Cut each sheet into four equal square pieces, yielding eight squares total.
03 -
In a small bowl, whisk together the beaten egg and 1 tablespoon of milk until combined.
04 -
Place one slice of ham on each pastry square, optionally spreading a thin layer of Dijon mustard on the ham before topping with a cheese slice. Season lightly with salt and pepper, then sprinkle fresh herbs if using.
05 -
Top each ham and cheese stack with another pastry square. Press edges gently to seal, then crimp with a fork to secure and add a decorative pattern.
06 -
Brush the entire surface of each pastry stack with the prepared egg wash to promote golden, glossy browning.
07 -
Arrange stacks on the baking sheet, spacing them apart to allow for expansion. Bake for 20–25 minutes until puffed and golden brown.
08 -
Remove from oven and let the stacks cool slightly on the baking sheet to allow layers to set and cheese to remain melty.