In a mixing bowl, combine olive oil, lemon juice, dried thyme, garlic powder, salt, and black pepper. Place the salmon fillets in the bowl and coat them well with the marinade. Let them marinate for at least 15 minutes.

While the salmon is marinating, trim the asparagus ends and toss them in olive oil, salt, and black pepper. Spread them evenly on a baking sheet lined with parchment paper.

Place the marinated salmon fillets on the grill and cook for about 4-5 minutes on each side, or until they flake easily with a fork. Make sure to oil the grill grates to prevent sticking.

While the salmon is grilling, place the baking sheet with the asparagus in the oven and roast at 400°F (200°C) for about 15-20 minutes, until tender and slightly charred.

Serve the grilled salmon on a plate with a side of roasted asparagus. Drizzle with extra lemon juice for brightness. Leftovers can be refrigerated for up to 2 days. A sprinkle of fresh parsley adds a lovely garnish.