In a bowl, combine olive oil, Dijon mustard, rosemary, thyme, garlic, salt, and black pepper.

Coat the beef tenderloin thoroughly with the marinade. Cover and refrigerate for at least 2 hours, preferably overnight.

Preheat your oven to 425°F (220°C).

In a large oven-safe skillet, heat a little olive oil over medium-high heat. Sear the tenderloin on all sides until browned, about 2-3 minutes per side.

Pour the beef broth and balsamic vinegar into the skillet around the tenderloin.

Transfer the skillet to the preheated oven. Roast for 45 minutes to 1 hour, or until the internal temperature reaches 135°F (57°C) for medium-rare.

Remove the roast from the oven and let it rest for 15-20 minutes. This allows the juices to redistribute.

For extra richness, melt butter into the pan juices and drizzle over the sliced beef before serving.

Use a sharp knife to slice the tenderloin into even pieces for serving.