Preheat your oven to 400°F and line a baking sheet with parchment paper.
Toss the cubed sweet potatoes and trimmed asparagus with 1 teaspoon of avocado oil, half the sea salt, and half the black pepper.
Spread the vegetables on the baking sheet and roast for 20 minutes until the sweet potatoes are tender and the asparagus is lightly charred.
While the vegetables roast, pat the sirloin steak dry with paper towels and season both sides with the remaining sea salt and black pepper.
Heat the remaining 1 teaspoon of avocado oil in a cast-iron skillet over medium-high heat until it begins to shimmer.
Place the steak in the hot skillet and sear for 3-4 minutes per side for medium-rare, creating a deep brown crust.
Reduce the heat to medium-low and add the ghee, smashed garlic clove, rosemary, and thyme to the side of the pan.
Tilt the pan slightly and use a large spoon to continuously baste the steak with the melting herb-infused ghee for 1 minute.
Transfer the steak to a cutting board and let it rest for 5 minutes to allow the juices to redistribute.
Slice the steak against the grain and serve alongside the roasted vegetables, drizzling any remaining pan juices over the meat.