Servings: 16 sliders 1 Tbsp olive oil 2 Tbsp unsalted butter 1 large or 2 medium yellow onions, thinly sliced 1/4 tsp sugar 1 oz au jus mix, made according to package instructions 3 cups water, to make the sauce, or to taste 16 Hawaiian sweet rolls 1/4 cup mayonnaise 1 lb deli pastrami or roast beef, thinly sliced 9 slices mild provolone cheese, not aged 2 Tbsp unsalted butter, melted, plus more to grease baking sheet 1 Tbsp sesame seeds
Preheat oven to 350˚F. Butter a rimmed baking sheet. Place a large skillet over medium/high heat with 1 Tbsp olive oil and 2 Tbsp butter. Add sliced onion and Sauté over medium heat for 5 minutes until softened, stirring occasionally.
Sprinkle with 1/4 tsp sugar and sautee uncovered 5 minutes until caramelized and golden, stirring often. Transfer to a plate. In the same pan, add 2 1/2 cups water and scrape the pan to deglaze.
Add the au jus seasoning (adding to taste) then bring to a boil, reduce heat and simmer according to package instructions. Add more water to taste if it’s too salty. Cut buns in half. Place the bottom half of dinner rolls on a buttered baking sheet and spread 1/4 cup mayo.
Layer folded slices of beef evenly over the rolls. Spread caramelized onions over your sliders. Cover the beef with sliced provolone. Place the top of buns over and brush the tops with 2 Tbsp melted butter then immediately sprinkle tops with sesame seeds.
Bake uncovered at 350˚F for 12-15 minutes, or until cheese is melted and tops are golden brown. Cut through the buns with a serrated knife to separate into individual sliders. Serve with warm au jus dip.