Unfold the puff pastry onto floured or marble surface. Using a rolling pin, roll out the puff pastry dough to half its thickness. Add a generous amount of Dijon mustard & spread out the mustard to completely cover the puff pastry. Cover the entire surface with the ham, overlapping as needed. Lastly, cover the ham with the cheese.
Starting at one end, roll up the puff pastry into a log shape, then cut 11 slits in the softened dough. Refrigerate the Ham & Cheese Puff Pastry for 10 minutes...the puff pastry will become chilled, making it easier to slice.
Slice the puff pastry into 12 pinwheels. Place the Ham & Cheese Puff Pastry Pinwheels on a parchment paper-lined baking sheet.
Bake the Ham & Cheese Puff Pastry Pinwheels for 20 minutes. Remove from the oven & serve immediately.