To achieve the best taste, the beef roast needs to be salted thoroughly, then left uncovered in the refrigerator for a few days. (This process is often termed “dry brining.”) Though the method requires planning and a few hours of oven time, the deliciously savory result is worth every minute.
To minimize cooking-day hassle, you can make the horseradish sauce up to two weeks ahead. While the meat rests after it’s been roasted, you’ll have time to attend to your other holiday dishes.
Cook’s note: If you’ve never made prime rib, keep in mind that “Frenching” the bones is a very specialized skill. This technique strips the meat away from the bone of a rib or chop to expose the bone cleanly. You can save yourself the time and stress by having your butcher French your prime rib before you bring it home.