Heat oven to 350 F.
Halve slider buns, creating top and bottom portions. Set top portion aside, leaving bottom portion in original container. Place bottom portion and container in baking dish to prevent sticking.
Layer Swiss cheese, salami and ham then cover with top buns.
Mix melted butter, Worcestershire sauce, brown sugar, Parmesan cheese, onion powder and garlic powder. Pour over sliders.
Cover with foil and bake 15 minutes then remove foil, sprinkle with everything bagel seasoning, if desired, and bake, uncovered, 10 minutes. Now enjoy!