Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper.
Trim the woody ends off the asparagus spears and place them on one side of the baking sheet.
Drizzle the asparagus with olive oil and sprinkle 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 in a thin layer over the top of the salmon fillet.
In a small bowl, combine the almond flour, lemon zest, chopped fresh parsley, and the remaining salt and pepper.
Press the almond flour mixture firmly onto the mustard-coated salmon to create an even crust.
Roast in the oven for 12 to 15 minutes, or until the salmon is flaky and the crust has turned a light golden brown.
Serve the salmon immediately alongside the roasted asparagus with an optional squeeze of fresh lemon juice.