mixed-color peppercorns (black, white, pink, and green)
boneless beef rib roast, at room temperature
kosher salt and black pepper
- Heat oven to 375° F. Place the peppercorns in a resealable plastic bag and crush with the bottom of a heavy pan.
- Place the beef in a large roasting pan and season with the crushed peppercorns and 1½ teaspoons salt, pressing gently to help the peppercorns adhere.
- Roast the beef to the desired doneness, 85 to 95 minutes for medium-rare (internal temperature registers 130° F*). Transfer to a cutting board, cover loosely with foil, and let rest for at least 15 minutes before slicing.
- Meanwhile, in a small bowl, combine the sour cream, horseradish, and ½ teaspoon each salt and black pepper. Serve with the beef.
- *Note: This is the temperature preferred by the Real Simple test kitchen, and it is considered safe by many experts. The U.S. Department of Agriculture’s recommendation for maximum safety is 15° to 20° F higher.