Preheat oven to 325°. In a small mixing bowl, combine salt 1/2 teaspoon pepper, oregano, rosemary, thyme and dry mustard. Brush roast with vinegar and rub with herb mixture. Roast uncovered for 1 hour and 10 minutes for medium doneness. Remove from oven and let rest, covered, 10 to 15 minutes. Blend or whisk together blue cheese, sour cream, Worcestershire sauce, remaining pepper, chives and celery salt. Slice roast and serve with blue cheese sauce.
All recipes provided by the Certified Angus Beef® brand.