Preheat your oven to 400°F for the asparagus.
Peel and cube the sweet potato, then boil in a pot of water until tender, about 12 to 15 minutes.
Trim the woody ends off the asparagus and toss the spears with half of the olive oil, sea salt, and black pepper.
Spread the asparagus on a baking sheet and roast for 10 to 12 minutes until tender-crisp.
While the vegetables cook, pat the salmon fillet dry with a paper towel and season both sides with salt and pepper.
Heat the remaining olive oil in a non-stick skillet over medium-high heat.
Place the salmon in the pan skin-side down and sear for 4 to 5 minutes until the skin is crispy, then flip and cook for another 2 to 3 minutes until cooked through.
Drain the sweet potatoes and mash them until smooth, adding a splash of hot water or a squeeze of lemon if needed for texture.
Plate the sweet potato mash, place the seared salmon on top, and serve the roasted asparagus alongside with a final squeeze of fresh lemon juice.