Prime Rib Sandwich

Tender, juicy prime rib is piled high on toasted garlic bread and topped with sautéed mushrooms and hot and sweet peppers for the ultimate Prime Rib Sandwich. Serve it French dip style with a cup of au jus! 

Prep Time: 15 mins

Cook Time: 30 mins

Total Time: 45 mins

Serves: 2


For the mushrooms: 
  • 1 Tablespoon olive oil or butter 
  • 8 oz. sliced mushrooms 
  • 1 large garlic clove, minced 
  • Kosher salt, to taste 
For the au jus: 
  • 4 Tablespoons beef drippings or butter 
  • 1 ½ Tablespoons flour 
  • 2 cups beef broth 
  • 1 Tablespoon Worcestershire 
  • ½ Tablespoon soy sauce 
  • Salt and pepper, to taste 
For the sandwiches: 
  • 2 bolillo, ciabatta, or French sandwich rolls 
  • 3 Tablespoons salted butter, at room temperature 
  • 2 large cloves garlic, minced 
  • 8-10 oz. thin sliced leftover prime rib 
  • 4 slices white American cheese 
  • Sautéed mushrooms, from above 
  • ¼ cup sliced sweet and hot peppers


Thinly slice your leftover prime rib and allow it to sit at room temperature while you prepare the other ingredients. 

For the mushrooms: 
  1. Heat the oil in a pan over medium-high heat. Add the mushrooms, spreading them evenly over the pan. Cook, undisturbed, for several minutes or until browned. Flip and continue to cook for an additional minute or two, adding the garlic for the last 30 seconds. Sprinkle with salt to taste. 
For the au jus
  1. Add the beef drippings to a sauce pot and heat over medium-high heat. Once it is simmering, whisk in the flour until the mixture is smooth and bubbly. 
  2. Slowly drizzle about ¼ cup of the beef broth into the flour mixture. It will bubble quite violently! Once it’s settled a bit, drizzle the rest of the broth in. Continue to cook until mixture is gently boiling and slightly thickened another few minutes. 
  3. Stir in Worcestershire and soy sauce. Remove from heat, then taste and season with salt and pepper as needed. 
For the sandwiches: 
  1. Broil the garlic bread. Mix together the butter and garlic cloves in a small bowl. Slice the rolls and slather the butter mixture evenly over both sides. Place them on a pan, butter side up, and broil for about 2 minutes, until brown and toasty. 
  2. Broil the meat and cheese. Take the bottom of each roll and stack each of them with half the prime rib, followed by the sliced cheese. Place the sandwiches back under the broiler for another 1.5-2 minutes, or until the cheese is melted. 
  3. Add toppings. Top the sandwiches with the sliced peppers, mushrooms, and the second garlic bread. Serve with warm au jus.

  • You can use any leftover prime rib for this recipe. Prime rib can be cooked and stored in the fridge for up to 4 days. We find it's easier to get nice thin slices after its refrigerated. 
  • The au jus and mushrooms can be prepared up to a day in advance and stored in the refrigerator. Reheat the au jus on the stovetop or in the microwave and whisk well before serving. 
  • This recipe makes two large sandwiches. Depending on who you're serving it to, you might be able to get two servings out of each sandwich. You can also double the recipe to feed more people. The au jus does not need to be doubled, and will easily serve 4-6 people.