Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper for easy cleanup.
Snap the woody ends off the asparagus spears and place them on one side of the prepared baking sheet.
Drizzle the asparagus with the extra virgin olive oil and season with a pinch of sea salt and black pepper, tossing to coat evenly.
In a small mixing bowl, whisk together the Dijon mustard, garlic powder, dried parsley, and fresh lemon juice until well combined.
Place the salmon fillet on the other side of the baking sheet and spread the mustard mixture generously over the top of the fish.
Sprinkle the almond flour over the mustard layer, pressing it down gently with your fingers to ensure it sticks and forms a crust.
Roast the salmon and asparagus in the oven for 12 to 15 minutes, depending on the thickness of the fillet, until the salmon flakes easily with a fork.
Remove from the oven and serve the salmon immediately alongside the roasted asparagus with an optional extra squeeze of lemon.