Preheat your oven to 400°F. Peel and cube the sweet potato, then toss with avocado oil and a pinch of salt and pepper.
Spread the sweet potatoes on a baking sheet and roast for 20-25 minutes until tender and slightly caramelized.
Pat the sirloin steak dry with paper towels and season both sides with the remaining sea salt and black pepper.
Heat a cast-iron skillet over medium-high heat. Once the pan is very hot, sear the steak for 3-4 minutes per side for medium-rare.
During the last 2 minutes of cooking, add the ghee, smashed garlic clove, parsley, and thyme to the skillet.
Tilt the pan slightly and use a spoon to continuously baste the steak with the melted herb ghee.
Remove the steak from the pan and let it rest on a cutting board for at least 5 minutes to lock in the juices.
While the steak rests, add the asparagus to the same skillet and sauté in the remaining pan juices for 3-5 minutes until bright green.
Slice the steak against the grain and serve immediately with the roasted sweet potatoes and sautéed asparagus.