Preheat your oven to 425°F.
Peel and cube the sweet potato. Boil the cubes until tender, about 10-12 minutes. Drain and transfer to a bowl.
Add the cannellini beans to the sweet potato and mash together until you reach a creamy consistency. Season with a pinch of salt and pepper if desired.
While the sweet potato is boiling, trim the tough ends of the asparagus. Toss the asparagus spears with half of the olive oil, salt, and pepper, then spread on a baking sheet.
Roast the asparagus in the preheated oven for about 10-12 minutes until tender but still crisp.
Meanwhile, heat a non-stick skillet over medium-high heat with the remaining olive oil. Pat the salmon fillet dry, then season with salt and pepper.
Sear the salmon for about 3-4 minutes per side, or until the exterior is nicely browned and the fish is just opaque in the center.
To serve, place a generous spoonful of sweet potato and bean mash onto each plate, top with the seared salmon, and arrange the roasted asparagus on the side.