Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Peel the sweet potato and cut it into uniform 1-inch cubes to ensure even roasting.
In a bowl, toss the sweet potato cubes with 0.25 tablespoons of olive oil, a pinch of sea salt, and black pepper.
Spread the potatoes on the baking sheet and roast for 15 minutes until they begin to soften.
While potatoes roast, season the beef fillet on all sides with garlic powder, fresh rosemary, and the remaining salt and pepper.
Heat the remaining 0.25 tablespoons of olive oil in a cast-iron skillet over medium-high heat and sear the beef for 2 minutes per side to develop a golden crust.
Add the broccoli florets to the baking sheet with the potatoes, tossing slightly, and place the seared beef in the center.
Return the sheet to the oven for 10 to 12 minutes, or until the beef reaches an internal temperature of 135°F for medium-rare.
Remove from the oven and let the beef rest for at least 5 minutes to lock in the juices before slicing and serving.