Roll puff pastry out on a floured surface to form a rectangle 6 inches by 14 inches. Trim edges.
Mix the honey and mustard together and spread over the pastry right up to the edges
Pat the slices of ham dry and lay on top of the honey/mustard.
Roll along the long length of the pastry until it reaches the middle. Then repeat with the other side.
Cut into 1/2 inches slices. I measure and mark them first, and then slice. Lay slices on baking tray lined with greaseproof paper. brush with the egg yolk mixture and bake in a preheated oven 190C for about 10 minutes until just turning golden.
When cooked remove from oven, lace on cooling rack and sprinkle with parmesan whilst still hot. Once fully cooled these can be stored in an airtight container for up to 3 days. Crisp up before serving in an oven at 200C for 3 minutes.