Preheat your oven to 425°F (220°C) for the asparagus and sweet potato.
Peel and dice the sweet potato into small cubes. Toss in a little olive oil, salt, and pepper, then spread evenly on a baking sheet.
Trim the asparagus ends, drizzle with a tiny amount of olive oil, and season lightly with salt and pepper. Place on the same or a separate baking sheet.
Roast the sweet potato cubes for about 20-25 minutes until tender, and roast the asparagus for 10-15 minutes until slightly crispy but still bright.
While the vegetables roast, pat the salmon fillet dry. Season both sides with salt and pepper.
Heat a nonstick skillet over medium-high heat. Sear the salmon fillet skin-side down (if applicable) for about 3-4 minutes, then flip and cook for an additional 3-4 minutes until just cooked through.
Once the sweet potato is soft, transfer to a bowl and mash until smooth. Stir in the nonfat Greek yogurt for creaminess; season with salt and pepper to taste.
Plate the seared salmon alongside a generous serving of sweet potato mash and the roasted asparagus, and serve immediately.