Preheat your oven to 400°F and line a baking sheet with parchment paper.
Peel and cube the sweet potato, then boil in a pot of water for 12-15 minutes until fork-tender.
Pat the cod fillets dry with a paper towel and season lightly with sea salt and black pepper.
Place the egg white in one shallow bowl and the almond flour in another bowl.
Dip each cod fillet into the egg white, then press into the almond flour until evenly coated on all sides.
Place the fish on the prepared baking sheet, drizzle with olive oil, and bake for 12-15 minutes until the crust is golden and fish flakes easily.
While the fish bakes, steam the asparagus for about 5 minutes until tender-crisp.
Drain the sweet potatoes and mash them until smooth, adding a tablespoon of the cooking water if needed to reach your desired consistency.
Serve the crispy cod alongside the sweet potato mash and steamed asparagus with a fresh lemon wedge for squeezing.