Preheat the oven to 375°F. Spray a 9x13-inch baking dish with nonstick cooking spray and set aside.
Add 2 cups beef broth to a large skillet and bring to a simmer, for about 5 minutes.
Add 1 pound deli sliced roast beef and stir it in until warmed, about 2 minutes.
Place the bottom half of the Hawaiian Rolls - cut side up into the baking dish.
Add 6 slices of provolone cheese on top, they will probably overlap.
Add the warmed roast beef and let the excess broth drip off.
Add the remaining 6 slices of provolone cheese on top.
Add the tops of the rolls.
In a small bowl, stir together 1/2 cup salted butter, melted, 1/2 Tablespoon dijon mustard, 1 teaspoon dried onion flakes and 1/2 teaspoon garlic powder.
Brush the butter sauce all over the rolls, use it all.
Add nonstick foil on top (or spray a large piece of foil with cooking spray). Bake covered for 20 minutes until the cheese is melted.
Take off the foil and bake for an additional 5 minutes or until browned. Cut into individual sliders and serve.
Notes
Please refer to my FAQ’s (Frequently Asked Questions) and ingredient list above for other substitutions or for the answers to the most common questions.