Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Trim the woody ends off the asparagus spears and place them on one side of the baking sheet, tossing with olive oil and half of the sea salt and black pepper.
Pat the salmon fillet dry with a paper towel and place it on the other side of the baking sheet, skin-side down.
Spread the Dijon mustard in a thin, even layer over the top of the salmon fillet to act as a binder for the crust.
In a small bowl, combine the almond flour, finely chopped parsley, chopped dill, garlic powder, and the remaining salt and pepper.
Press the herb and almond mixture firmly onto the mustard-coated salmon to create a thick, even crust.
Roast in the center of the oven for 12 to 15 minutes, or until the salmon flakes easily with a fork and the asparagus is tender and slightly charred.
Remove from the oven and serve immediately with a fresh squeeze of lemon juice over both the fish and vegetables.