Preheat your grill or grill pan to medium-high heat, ensuring the grates are clean and lightly oiled.
In a small glass bowl, whisk together the extra virgin olive oil, fresh lemon juice, lemon zest, chopped dill, parsley, sea salt, black pepper, and garlic powder.
Place the salmon fillet on a plate and brush half of the lemon-herb mixture over the top and sides.
Toss the trimmed asparagus spears with the remaining marinade until they are evenly coated.
Place the salmon on the grill, skin-side down, and cook for about 4 to 5 minutes until the skin is crispy and releases easily.
Carefully flip the salmon and grill for another 2 to 3 minutes, or until it reaches your desired level of doneness.
While the salmon cooks, place the asparagus on the grill and cook for 3 to 5 minutes, turning occasionally until tender and slightly charred.
Remove everything from the grill and serve immediately with an extra squeeze of fresh lemon if desired.