INGREDIENTS:

1 Standing Rib Roast (7 to 9 pounds)
1 1/2 teaspoons freshly ground black pepper
1 1/2 cups good mayonnaise
3 tablespoons Dijon mustard
1 1/2 tablespoons whole-grain mustard
1 tablespoon prepared horseradish
1/3 cup sour cream

DIRECTIONS:

Two hours before roasting, remove the meat from the refrigerator and allow it to come to room temperature.  You will note I am not using any SALT in this recipe.  Mustard has enough salt in it already.

Be sure your oven is squeaky clean because at a temperature of 500 degrees anything baked on the sides or bottom of your oven will fill your kitchen with smoke!

Preheat the oven to 500 degrees F

Place the oven rack on the second lowest position.
Place the roast in a pan large enough to hold it comfortably, bone-side down, and spread the top thickly with the pepper. Roast the meat for 45 minutes. Without removing the meat from the oven, reduce the oven temperature to 325 degrees F and roast for another 30 minutes. Finally, increase the temperature to 450 degrees F and roast for another 15 to 30 minutes, until the internal temperature of the meat is 125 degrees F. Be sure your thermometer is in the center of the roast. The total cooking time will be between 1 1/2 and 1 3/4 hours. Remove the roast from the oven and transfer it to a cutting board. Cover it tightly with aluminum foil and allow the meat to rest for at least 20 minutes. Carve  and arrange on platter.

Mustard Horseradish Cream:
Whisk together the mayonnaise, mustards, horseradish, sour cream, and salt in a small bowl. Serve along side your carved roast.