Easy French Dip Sliders

INGREDIENTS
2 tablespoons unsalted butter, softened
1 package Hawaiian sweet rolls
1 pound thinly sliced roast beef deli meat
12 slices provolone cheese, divided
1 1/2 cups French fried onions
For the sauce:
8 tablespoons unsalted butter, melted
1 packet Au Jus seasoning mix, divided
1 teaspoon Worcestershire sauce
1/2 teaspoon garlic powder
1/2 teaspoon onion powder
1/2 teaspoon Kosher salt

PREPARATION
Preheat oven to 350°F and grease a 9×13-inch baking dish with the 2 tablespoons softened butter.
Slice the package of rolls in half without separating the rolls from each other. Place the bottom half of the rolls in the prepared baking dish.
Top rolls with six slices of the provolone cheese, the roast beef, and the French fried onions.
Top with remaining six slices of cheese and the top half of the rolls.
In a small bowl, mix together the melted butter, 1 tablespoon of the Au Jus mix, Worcestershire sauce, garlic powder, onion powder, and salt. Pour mixture evenly over sliders, making sure all rolls are coated.
(Note: You can prepare sliders ahead up until this point. To make ahead, cover with foil and let chill in fridge up to overnight. When ready to bake, remove foil and increase baking time by 5-10 minutes.)
Bake, uncovered, until rolls are golden brown and cheese has melted, 15-20 minutes.
While sliders bake, add remaining Au Jus mix to a small saucepan over medium heat. Whisk in 2 cups cold water and bring to a boil. Reduce to a simmer and cook until slightly thickened.
Cut sliders apart with a knife and serve with Au Jus sauce. Enjoy!