Ingredients:

  • 500g yellow onions, thinly sliced
  • 28g unsalted butter
  • 15ml balsamic vinegar
  • 4g brown sugar
  • 3g kosher salt
  • 680g ground beef (80/20 chuck)
  • 15ml Worcestershire sauce
  • 3g garlic powder
  • salt and black pepper to taste
  • 8 slices hearty rye bread
  • 225g Swiss cheese slices
  • 56g unsalted butter, softened
  • 30ml mayonnaise
  • 60ml Thousand Island dressing

Instructions:

  1. Melt 28g butter in a skillet over medium-low heat. Add sliced onions and salt. Cook for 25–30 minutes, stirring occasionally, until mahogany-colored. Deglaze with balsamic vinegar and brown sugar in the final 5 minutes. Remove and set aside.
  2. In a mixing bowl, gently combine ground beef with Worcestershire sauce and garlic powder. Form into 4 oval patties slightly larger than the bread slices. Season the exterior with salt and pepper.
  3. Wipe out the skillet and increase heat to medium-high. Sear patties for 3-4 minutes per side until cooked through. Remove and tent with foil.
  4. Mix the 56g softened butter with 30ml mayonnaise. Spread this mixture onto one side of each bread slice.
  5. Assemble using the CPC (Cheese-Patty-Cheese) method: Place bread butter-side down in the skillet, add a slice of cheese, the beef patty, a portion of onions, another slice of cheese, and the second bread slice (butter-side up).
  6. Grill on medium heat for 3-4 minutes per side, pressing gently with a flat spatula, until the bread is a deep mahogany brown and cheese is fully melted. Serve with Thousand Island dressing.