Preheat the oven to 200 degrees Celsius. Peel the sweet potato and cut it into cubes; toss on a baking sheet with half of the olive oil, salt and pepper, and roast for approximately twenty-five minutes until tender.
Break off the woody ends of the asparagus and place them in the oven with the sweet potato for the last ten minutes so they become just tender-crisp.
Meanwhile, heat the remaining oil in a skillet and pan-fry the salmon skin-side down for three to four minutes, then flip and cook for another two minutes. Season with salt, pepper and dill and serve with the sweet potato and asparagus and a lemon wedge.