Pre-heat oven to 375F / 190C. Line a large baking sheet with parchment paper.
Unroll the puff pastry and with a rolling pin gently roll a couple of times to even it out.
Depending on how big the sheet is cut into 6-9 squares. I got 9 squares, my puff pastry sheet was 13x11 / 32x27cm approximately.
Wrap 3-5 spears of asparagus with a slice of prosciutto and set aside.
In the middle of each square place 1-2 thin slices of cheese.
On top of the cheese place a prosciutto wrapped bundle, place another piece of cheese on top of the asparagus.
Fold the puff pastry over the asparagus, wetting the ends to seal. Place the bundles on the prepared baking sheet. If you wish you can brush with a little milk and sprinkle with a dash of black pepper if desired. Bake approximately 15-20 minutes, in the pre-heated oven until golden brown. Serve immediately.
Notes
Any leftovers should be placed in an airtight container and refrigerated. They will keep for up to 3-4 days in the fridge. Re-heat in the oven or microwave.