Preheat your oven to 425°F (220°C).
Mince the garlic cloves and finely chop the fresh rosemary and thyme leaves.
Pat the beef tenderloin dry with a paper towel and rub with 0.5 tbsp of olive oil, followed by the minced garlic, rosemary, thyme, sea salt, and black pepper.
Place the beef on a roasting pan and cook for 15-20 minutes, or until the internal temperature reaches 135°F for medium-rare.
While the beef roasts, trim the woody ends off the asparagus and toss with the remaining 0.5 tbsp of olive oil.
Add the asparagus to the roasting pan for the final 10 minutes of the beef's cooking time.
Peel and dice the sweet potato, then steam or boil until tender; mash until completely smooth and silky.
Remove the beef and asparagus from the oven; let the beef rest for at least 5-10 minutes before slicing into medallions.
Plate the sliced beef tenderloin with the roasted asparagus and sweet potato mash.