1 (5 pound) beef prime rib roast, 2 to 3 ribs
1 tablespoon black pepper
1 cup KRAFT Zesty Italian Dressing
1 1/2 cups KRAFT Mayo Real Mayonnaise, divided
1/4 cup KRAFT Prepared Horseradish
1/4 cup KRAFT Honey-Mustard Dressing
1/2 teaspoon dried thyme leaves

Place meat in large glass dish; sprinkle evenly with pepper. Pour Italian dressing over meat; cover and marinate in refrigerator at least 1 hour.
Preheat oven to 325 degrees F. Remove meat from marinade; discard marinade. Place meat, fat side up, in shallow roasting pan. Bake 2 to 2-1/2 hours or until meat thermometer inserted into thickest part of meat registers 130 degrees F to 135 degrees F for medium-rare doneness. Remove from oven. Cover and let stand 20 min. before carving.
Meanwhile, mix 1 cup of the mayo and horseradish in small serving bowl. Mix remaining 1/2 cup mayo, honey-mustard dressing and thyme in a separate small serving bowl. Serve both sauces with the meat.
Yield: 15 servings

Source: http://food.yahoo.com