Preheat oven to 325°.
Split rolls in half.
Fit bottom halves into a lightly greased 4 quart, 10" X 15" Pyrex dish.
Layer ham, then cheese onto bottoms.
Finish off with roll tops and set aside.
Whisk together melted butter, brown sugar, poppy seeds, dry mustard and Worcestershire sauce.
Pour/brush mixture evenly over tops of sandwiches.
Cover very tightly with foil.
(At this point can refrigerate overnight if needed.)
Bake covered at 325° for 25 minutes.
Remove foil and bake for an additional 5-10 minutes until golden brown.
Serve immediately.