Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Peel the sweet potato and cut it into small, uniform half-inch cubes for even cooking.
Toss the sweet potato cubes with half of the avocado oil and a pinch of sea salt on the baking sheet.
Roast the sweet potatoes for 15 minutes.
While potatoes roast, trim the woody ends off the asparagus spears.
Add the asparagus to the baking sheet, tossing with the potatoes, and roast for an additional 10 minutes until tender.
Heat the remaining avocado oil in a non-stick or cast-iron skillet over medium-high heat.
Season the salmon fillet with salt and pepper, then place it in the hot pan skin-side down.
Sear the salmon for 4-5 minutes per side until the skin is golden and crisp and the flesh is just opaque.
Plate the salmon alongside the roasted vegetables and finish with a fresh squeeze of lemon juice.