Preheat your oven to 400°F and line a large baking sheet with parchment paper.
Peel and cube the sweet potato into 1/2-inch pieces, then toss them in a bowl with the avocado oil and half of the sea salt, black pepper, and garlic powder.
Spread the sweet potatoes evenly on the baking sheet and roast for 15 minutes.
Trim the woody ends off the asparagus, add them to the baking sheet with the potatoes, and roast for an additional 10 minutes until the vegetables are tender.
While the vegetables finish roasting, pat the salmon fillet dry with a paper towel and season both sides with the remaining salt, pepper, and garlic powder.
Heat the ghee in a stainless steel or cast-iron skillet over medium-high heat until shimmering.
Place the salmon in the pan, skin-side down, and sear for 4-5 minutes until the skin is golden and crispy.
Carefully flip the fillet and cook for another 2-3 minutes until the salmon is just cooked through.
Plate the salmon alongside the roasted sweet potatoes and asparagus, finishing the entire dish with a fresh squeeze of lemon juice.