Set your oven to 350 degrees Fahrenheit and grease a 9x13 inch baking pan with cooking spray.
Combine melted butter, brown sugar, Dijon mustard, Worcestershire sauce, poppy seeds, and dried minced onion in a bowl.
Slice the rolls horizontally and place the bottom halves evenly in the baking dish.
Layer half of the sliced ham over the bottom rolls followed by the Swiss cheese, then add the remaining ham on top.
Place the tops of the rolls over the layered fillings and pour the butter mixture evenly over all the sliders.
Cover the dish tightly with foil and bake for 15 minutes.
Take off the foil and continue baking the sliders for another 10 minutes until the tops are nicely browned.
Remove from oven, slice into individual sliders, and serve while warm.