Preheat your grill or a cast-iron grill pan over medium-high heat until it is hot and ready for searing.
Pat the salmon fillet dry with a paper towel and rub it evenly with the smoked paprika, garlic powder, sea salt, and black pepper.
Trim the woody ends off the asparagus spears and toss them with half of the extra virgin olive oil.
Place the salmon on the grill skin-side down and cook for 4 to 5 minutes, then carefully flip and cook for another 3 minutes until the fish flakes easily with a fork.
Add the asparagus to the grill alongside the salmon during the last 4 minutes of cooking, turning occasionally until tender-crisp with light char marks.
In a small bowl, whisk together the remaining olive oil, fresh lemon juice, and Dijon mustard until the dressing is fully emulsified.
Arrange the grilled asparagus on a plate, top with the smoky salmon fillet, and drizzle the zesty lemon dressing over the entire dish before serving.