In a mixing bowl, combine 1 cup of softened salted butter with 3-4 minced garlic cloves, 2 teaspoons of fresh rosemary, 2 teaspoons of fresh thyme, 2 tablespoons of Dijon mustard, 2 teaspoons of Worcestershire sauce, 1 teaspoon of kosher salt, and freshly cracked black pepper to taste. Mix until well blended.

Remove the bone-in prime rib roast from the refrigerator, allowing it to sit at room temperature for about 1 hour. Trim any excess fat and tie with twine for a neat presentation.

Preheat your oven to a gentle 250°F (120°C). Line a roasting pan with a rack and place the prime rib on the rack, pat it dry with paper towels.

Generously rub the prepared compound butter all over the surface of the prime rib, ensuring it is completely coated.

Cook the Garlic and Herb Prime Rib Roast for about 2 1/2 to 3 hours, or until the internal temperature reaches approximately 100°F (38°C) at the center.

Once the roast has reached 100°F, increase the oven temperature to 400°F (200°C) and continue roasting until the internal temperature reaches your desired doneness: 125°F (52°C) for rare, or 135°F (57°C) for medium.

After achieving the desired internal temperature, remove the roast from the oven and let it rest for at least 30 minutes.

While the roast rests, make the gravy by whisking ⅓ cup of flour into the remaining fat over medium heat, then gradually add in 3 cups of beef broth until the mixture thickens.

After resting, carefully carve the Garlic and Herb Prime Rib Roast against the grain into thick slices and serve warm, accompanied by gravy.