Best Prime Rib Recipe with Au Jus - Traeger Grills

Ingredients

• 1 3- to 4-bone standing rib roast (10 to 12 lb)
• kosher salt
• Traeger Prime Rib Rub, as needed
• 1 Bunch sage
• 1 Bunch rosemary
• 1 Bunch thyme
• 1 Bunch parsley
• 3 Tablespoons mayonnaise
• 2 Tablespoons Dijon mustard
• 2 Tablespoons Worcestershire sauce
• 3 Medium carrots, cut into 1-inch pieces
• 3 celery stalks, cut into 1-inch pieces
• 1 Large yellow onion, cut into 1-inch pieces
• 2 bay leaves
• 3 garlic cloves, smashed
• 1 Tablespoon olive oil
• 4 Cups beef stock
• freshly ground black pepper
• 1/4 Cup prepared horseradish
• 2 Tablespoons mayonnaise
• 2 Tablespoons sour cream
• 1/2 Teaspoon Traeger Prime Rib Rub