01 -
Preheat your oven to 350°F (175°C). Grease or line a 9×13-inch baking dish with parchment paper. Slice the slider buns in half horizontally, keeping the tops and bottoms intact. Place the bottom halves of the buns in the prepared baking dish.
02 -
Layer the roast beef evenly over the buns. If using onions, sauté them in butter until soft and golden, then layer them over the roast beef. Add a slice of provolone cheese to each bun. Place the tops of the buns over the cheese.
03 -
In a small bowl, mix the melted butter, garlic powder, onion powder, Worcestershire sauce, sesame seeds (if using), and parsley. Brush this mixture generously over the tops of the buns.
04 -
Cover the dish with foil and bake for 15 minutes. Remove the foil and bake for an additional 5–7 minutes, or until the tops are golden brown and the cheese is melted.
05 -
While the sliders are baking, combine the beef broth, Worcestershire sauce, soy sauce, garlic powder, and black pepper in a small saucepan. Bring to a simmer over medium heat and cook for 5 minutes. Keep warm.
06 -
Serve the sliders warm with the au jus on the side for dipping.