Preheat & Prep Pan: Preheat your oven to 350°F (175°C). Line a 9x13-inch baking dish with parchment paper or grease lightly with nonstick cooking spray.

Slice the Hawaiian Rolls: Keeping all 12 rolls connected as a single slab, use a large serrated knife to slice horizontally through the middle, creating a top slab and a bottom slab. Place the bottom slab into the prepared baking dish.

Layer Ham & Cheese: Layer half of the Swiss and provolone cheese slices across the bottom buns. Evenly fold and arrange the sliced ham over the cheese. Top the ham with the remaining cheese slices (this double-cheese barrier prevents soggy buns). Place the top bun slab over the cheese.

Whisk the Savory Glaze: In a small bowl, whisk together melted butter, Dijon mustard, Worcestershire sauce, brown sugar, poppy seeds, onion powder, and garlic powder until smooth and well emulsified.

Brush Glaze Generously: Use a silicone pastry brush to evenly coat the tops and sides of the rolls with the glaze, allowing the savory butter mixture to seep into the nooks and crevices between each roll.

Cover & Bake: Cover the baking dish loosely with aluminum foil (tenting slightly so cheese doesn't stick). Bake for 12 to 15 minutes until the cheese is completely melted and bubbly. Remove foil and bake uncovered for an additional 4 to 6 minutes until the tops are golden brown and lightly crisp.

Rest, Slice & Serve: Let rest for 5 minutes before pulling apart or cutting into individual sliders with a chef's knife. Serve hot and gooey!