Prime Rib Sandwich

Total Time Prep: 30 min. Cook: 5 min.
Yield 4 servings
Test Kitchen Approved
Leftover prime rib has never tasted as good as when it's piled high with buttery sauteed onions and mushrooms, horseradish mayo and peppery arugula on a sturdy roll.

Ingredients

  • 1/2 cup butter
  • 1 large onion, thinly sliced
  • 8 ounces sliced fresh mushrooms
  • 1 garlic clove, minced
  • 1 package au jus gravy mix
  • 1/2 cup water
  • 3/4 cup mayonnaise
  • 2 tablespoons prepared horseradish
  • 1/2 teaspoon coarsely ground pepper
  • 1 pound leftover cooked prime rib, thinly sliced
  • 3 cups fresh arugula
  • 1 loaf French bread or French baguette, sliced in half horizontally
  • 6 slices provolone cheese

Directions

  1. [Photographer/stylist: I changed the amount of water, can you confirm the mushrooms and onions aren't like soup?- MK}
  2. In a large skillet, cook onions and mushrooms in butter until tender. Add garlic, cook one minute longer. Add gravy mix and water, stir to combine. Cook until liquid has reduced slightly. Remove from heat.
  3. In a large bowl, combine mayonnaise, horseradish, chives and pepper. Spread over bottom of French bread. Top with sliced prime rib, mushroom-onion mixture and provolone cheese.
  4. Preheat broiler. Place sandwich on a baking sheet. Broil 3-4 in. from heat until cheese is melted, 2-4 minutes.
  5. Top with fresh arugula and top of bread. Cut into serving size pieces.

Nutrition Facts

1 sandwich: 2726 calories, 65g fat (25g saturated fat), 162mg cholesterol, 6645mg sodium, 432g carbohydrate (18g sugars, 15g fiber), 99g protein.

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