Preheat oven to 350°F. Slice the rolls in half horizontally without separating them. Place the bottom slab in a 9x13 baking dish, layer with roast beef and provolone, then replace the top slab.

Stir together melted butter, garlic powder, onion powder, and 1 teaspoon Worcestershire. Brush over the tops generously.

Cover loosely with foil and bake 15 minutes. Remove foil and bake 5-8 minutes more until golden brown and bubbly.

While the sliders bake, simmer beef broth, 1 tablespoon butter, and remaining 1 teaspoon Worcestershire in a small saucepan. Keep warm.

Let sliders rest 5 minutes, then cut along the roll lines. Serve with the warm au jus for dipping.