Leftover Prime Rib French Dip Sandwiches
Transform your leftover prime rib into the ultimate French dip sandwich. Tender slices of prime rib are warmed in rich beef au jus and piled high on crusty French bread, creating a restaurant-quality meal in just 20 minutes. The warm dipping sauce keeps every bite incredibly juicy.
Equipment
- Medium saucepan for warming au jus and beef
- Sharp knife for slicing prime rib thin
- Cutting board
- Baking sheet for toasting bread
Ingredients
For the Sandwiches
- 1 pound leftover prime rib sliced thin
- 4 French bread rolls or hoagie rolls split lengthwise
- 4 slices provolone cheese optional
- 2 tablespoons butter softened
For the Au Jus
- 2 cups beef broth low sodium recommended
- 1 tablespoon Worcestershire sauce
- 1 teaspoon garlic powder
- 1/2 teaspoon onion powder
- Salt and black pepper to taste
Optional Toppings
- 1 medium onion sliced and caramelized
- 2 tablespoons prepared horseradish or horseradish mayo
Instructions
- Prepare the au jus by combining beef broth, Worcestershire sauce, garlic powder, and onion powder in a medium saucepan. Bring to a simmer over medium heat. Season with salt and pepper to taste.
- While the au jus heats, slice your leftover prime rib into thin strips, about 1/8 to 1/4 inch thick. Thinner slices warm through faster and are easier to eat.
- Preheat your oven to 400 degrees F. Split the French bread rolls and spread butter on the cut sides. Place on a baking sheet cut-side up.
- Toast the buttered rolls in the oven for 3-4 minutes until lightly golden and crispy on the edges. Watch carefully to prevent burning.
- Reduce the au jus to a gentle simmer. Add the sliced prime rib to the warm broth and let it heat through for 2-3 minutes. Do not boil or the meat will become tough.
- If using cheese, place a slice of provolone on each toasted roll bottom and return to the warm oven for 1 minute to melt.
- Using tongs, lift the warm prime rib from the au jus, letting excess liquid drip off, and pile generously onto each roll. Add caramelized onions and horseradish if desired.
- Ladle the hot au jus into small bowls for dipping. Serve immediately while everything is hot and the bread is still crispy.
Notes
Tips for Success:
- Slice the prime rib as thin as possible for the most tender bites.
- Never boil the meat in the au jus - just warm it gently to prevent overcooking.
- Use any leftover drippings or gravy from the original prime rib roast to enrich the au jus.
- French bread with a crispy crust works best - it holds up to dipping without getting soggy too quickly.