Preheat your oven to 425°F (218°C) and line a large baking sheet with parchment paper.
Peel and cube the sweet potato into 1/2-inch pieces. Toss them on one side of the baking sheet with half of the olive oil and a pinch of salt and pepper.
Roast the sweet potatoes for 10 minutes to give them a head start.
While potatoes roast, mince the garlic and finely chop the fresh rosemary and thyme.
In a small bowl, combine the remaining olive oil, minced garlic, rosemary, thyme, salt, and pepper to create a herb paste.
Pat the beef tenderloin dry with a paper towel and rub the herb paste evenly over all sides of the meat.
Remove the baking sheet from the oven. Move the potatoes to one side, place the beef tenderloin in the center, and add the trimmed asparagus to the remaining space.
Return the sheet to the oven and roast for 15-20 minutes, or until the beef reaches an internal temperature of 135°F for medium-rare.
Remove from the oven and transfer the beef to a cutting board. Let it rest for 5-10 minutes to allow the juices to redistribute.
Slice the beef into thick medallions and serve alongside the roasted sweet potatoes and asparagus.