Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Snap the woody ends off the asparagus and place them on one side of the baking sheet.
Drizzle the asparagus with olive oil and season with half of the sea salt and black pepper, tossing to coat evenly.
Pat the salmon fillet dry with a paper towel and place it on the other side of the baking sheet.
Spread the Dijon mustard evenly over the top of the salmon to act as a binder for the crust.
In a small bowl, combine the almond flour, garlic powder, dried parsley, and the remaining salt and pepper.
Press the almond flour mixture firmly onto the mustard-coated salmon until a golden crust forms.
Roast in the oven for 12 to 15 minutes, or until the salmon flakes easily with a fork and the asparagus is tender.
Squeeze fresh lemon juice over the entire dish before serving to brighten the flavors.