Preheat the oven to 200 degrees Celsius. Peel the sweet potato and cut it into cubes. Toss the cubes with olive oil, salt and pepper, and roast for twenty-five minutes until tender.
Meanwhile, steam the green beans for about eight minutes over boiling water until tender-crisp.
Season the salmon fillet with salt and pepper. Pan-fry the salmon skin-side down in a hot pan for four minutes until crispy, then briefly flip.
Arrange the sweet potato and green beans on a plate. Place the salmon on top, squeeze lemon over, and finish with fresh dill.