You will need two 9 x 13 pans.
Place the bottoms of 12 rolls in each pan.
Place ham (about 2 shaved slices or so) on the rolls.
Cut the cheese slices into 4 parts and place 2 small pieces on each sandwich.
Put the dinner roll tops on. In a saucepan, mix butter, dijon mustard, Worcestershire sauce, garlic powder and onion powder.
Wait until all butter is melted and then pour the melted mixture over the ham sandwiches.
Sprinkle the buns with poppy seeds and cover with foil.
Preheat oven to 350 and uncover sandwiches.
Bake at 350 for 15-20 minutes and serve.