Chef John's Perfect Prime Rib

Use Chef John's easy "mathematical method," and you'll get the best prime rib, cooked to a perfect medium rare, every time.

Ingredients

• 1 (4 pound) prime rib roast
• 0.25 cup unsalted butter, softened
• 1 tablespoon freshly ground black pepper
• 1 teaspoon herbes de Provence
• kosher salt to taste

Steps

1. Place prime rib roast on a plate and bring to room temperature, 2 to 4 hours.
2. Preheat an oven to 500 degrees F (260 degrees C).
3. Combine butter, pepper, and herbes de Provence in a bowl; mix until well blended. Spread butter mixture evenly over entire roast. Season roast generously with kosher salt.
4. Roast the 4-pound roast in the preheated oven for 20 minutes. (If your roast is larger or smaller than 4 pounds, see footnote to calculate cooking time.)
5. Turn oven off and, leaving the roast in the oven with the door closed, let the roast sit in the oven for 2 hours.
6. Remove roast from the oven, slice, and serve.