Ingredients:

  • 2 Tbsp Unsalted Butter (30 g)
  • 3 large Yellow Onions, thinly sliced (450 g)
  • 1/2 tsp Dried Thyme
  • 1/4 cup Beef Stock (low sodium, 60 ml)
  • To taste Salt and Black Pepper
  • 1 lb Lean Ground Beef (80/20 Chuck, 450 g)
  • 1 Tbsp Worcestershire Sauce (15 ml)
  • 1/2 tsp Garlic Powder (for beef)
  • 1 package Hawaiian Sweet Rolls (12 rolls)
  • 4 oz Sharp Cheddar Cheese, sliced or grated (115 g)
  • 4 oz Gruyère Cheese, sliced or grated (115 g)
  • 3 Tbsp Unsalted Butter, melted (45 g, for topping)
  • 1/2 tsp Garlic Powder (for topping)
  • 1 tsp Dried Parsley or Poppy Seeds (Optional)

Instructions:

  1. Sauté Slowly: Melt the 2 Tbsp butter in a heavy-bottomed skillet over medium-low heat. Add the sliced onions, a pinch of salt, and the dried thyme.
  2. Cook Down: Cook, stirring occasionally (every 5-7 minutes), for 20-25 minutes until the onions are deep golden brown and sticky. Do not rush this step.
  3. Deglaze: Add the 1/4 cup beef stock and scrape up any brown bits from the bottom of the pan. Cook until the liquid has evaporated and the onions are jammy. Set aside.
  4. Brown the Beef: Increase the heat to medium-high in the same skillet. Add the ground beef and season with Worcestershire sauce, garlic powder, salt, and pepper.
  5. Crumble and Drain: Break up the beef as it cooks. Cook until fully browned. Drain off any accumulated fat and set the beef aside.
  6. Preheat and Prep: Preheat the oven to 375°F (190°C). Lightly grease the 9x13 inch baking dish.
  7. Slice Rolls: Carefully slice the entire block of rolls horizontally, keeping the top half attached to the bottom half. Place the bottom halves into the prepared baking dish.
  8. Layer the Cheese Base: Sprinkle half of the shredded Gruyère and Cheddar mix evenly over the bottom layer of rolls.
  9. Add Filling: Spread the cooked, drained ground beef evenly over the cheese.
  10. Add Onions: Spoon the caramelised onion mixture over the layer of beef.
  11. Top with Cheese: Sprinkle the remaining half of the Gruyère and Cheddar mix over the onions.
  12. Place Top: Carefully place the top half of the rolls back onto the filling.
  13. Prepare Topping: In a small bowl, melt the remaining 3 Tbsp butter. Whisk in the 1/2 tsp garlic powder.
  14. Brush: Generously brush the top of the rolls with the garlic butter mixture. Sprinkle with poppy seeds or dried parsley, if desired.
  15. Bake Covered (Steam): Cover the baking dish tightly with foil. Bake for 10 minutes. (This melts the cheese and keeps the buns soft.)
  16. Bake Uncovered (Brown): Remove the foil and bake for another 8-10 minutes, or until the cheese is bubbling and the tops of the rolls are golden brown and slightly crisp.
  17. Rest and Serve: Remove from the oven and let rest for 5 minutes before slicing along the original lines to separate the individual sliders. Serve piping hot.