Preheat oven to 350 degrees Lightly grease a 9x13 casserole dish.

Cut the Hawaiian roll loaf through the middle. Place bottom half of the roll loaf in the casserole dish.

Add the ham and sliced swiss cheese to the bottom of the rolls and replace the top of the roll loaf.

Add Worcestershire sauce, Dijon mustard, poppy seeds, and onion powder to the melted butter. Coat the top and sides of the sliders with the melted butter mixture.

Bake, covered, for approximately 25 minutes. Uncover and bake an additional 5 minutes. Individually slice each slider in the casserole dish to separate before serving.