Ingredients:

  • 120 ml (1/2 cup) Sour cream
  • 45 ml (3 tbsp) Prepared horseradish, drained
  • 15 ml (1 tbsp) Fresh chives, finely minced
  • 5 ml (1 tsp) Lemon juice
  • 1.25 ml (1/4 tsp) Coarse kosher salt
  • 340g (12 oz) Leftover prime rib, sliced paper-thin against the grain
  • 2 Large hoagie rolls
  • 60g (4 slices) Provolone cheese
  • 30g (2 tbsp) Unsalted butter, softened
  • 120 ml (1/2 cup) Leftover Au Jus or beef consommé
  • 30g (1/4 cup) Caramelized onions

Instructions:

  1. Whisk together the sour cream, horseradish, lemon juice, chives, and salt in a small bowl. Refrigerate for at least 10 minutes to allow flavors to meld.
  2. Thinly slice the cold leftover prime rib against the grain to ensure maximum tenderness.
  3. Split the hoagie rolls and spread softened butter on the cut sides. Toast face-down in a skillet over medium heat until golden brown.
  4. Place cheese slices on the bread for the last 30 seconds of toasting. Cover the pan with a lid to melt the cheese.
  5. Heat the au jus in a small saucepan until steaming (approx. 150°F/65°C). Do not boil.
  6. Using tongs, dip beef slices into the warm au jus for 10–15 seconds to take the chill off without overcooking.
  7. Layer the warm beef and caramelized onions onto the cheesy rolls. Top with a generous dollop of horseradish sauce and serve with a side of au jus.