Cut rolls in half and place a slice of Polk's Sliced Ham on each. Cut the Swiss cheese into fourths and place on the roll. Replace the top of the rolls and bunch them closely together into a baking dish. In a medium bowl, whisk together poppy seeds, dijon mustard, melted butter, onion powder and Worcestershire sauce. Pour sauce over the rolls, just covering the tops. Cover with foil and let them sit for 10 minutes. Bake at 350 degrees for 10 minutes or until cheese is melted. Uncover and cook for additional 2 minutes until tops are slightly browned and crisp. Serve warm.