Combine the grated ham, butter, poppy seeds, mustard, onion, and Worcestershire sauce. Delete for now if not.

By taking the rolls out of the tray and slicing them in half, you may divide them. Keep the individual rolls together. Return the tray's bottom to it. On each side, spread the mixture.

If using, scatter small chunks of sliced ham over the butter mixture. Put the top layer of rolls back on top after adding the shredded cheese.

Wrap the tray tightly with foil, covering the entire surface. For about 20 minutes, bake at 350°F until the cheese melts.

Serve heated after slicing between the buns with a sharp knife.