01 - Remove beef from refrigerator 30 minutes prior to cooking to reach room temperature. Preheat oven to 400°F (gas mark 6).
02 - Combine olive oil, Dijon mustard, parsley, rosemary, thyme, garlic, sea salt, and black pepper in a small bowl until a paste forms.
03 - Pat beef dry with paper towels. Arrange onion, carrots, and celery in a roasting pan to create a vegetable trivet; place beef on top.
04 - Rub the herb paste evenly over the entire surface of the beef, pressing gently to ensure adhesion.
05 - Roast in preheated oven at 400°F for 20 minutes to develop crust.
06 - Lower oven temperature to 350°F (gas mark 4). Roast for an additional 1 hour 10 minutes, or until the internal temperature reaches 130°F for medium-rare or 140°F for medium doneness.
07 - Remove beef from oven, cover loosely with foil, and rest for at least 20 minutes to allow juices to redistribute.
08 - Slice beef against the grain and serve with pan juices and roasted vegetables as desired.