Preheat your oven to 400°F (200°C) and line a large rimmed baking sheet with parchment paper for easy cleanup.
Pat the Alaskan cod fillet dry with a paper towel to ensure a clean sear and place it on one side of the prepared baking sheet.
Trim the woody ends off the asparagus spears and arrange them in a single layer on the other side of the baking sheet.
In a small glass bowl, whisk together the olive oil, finely chopped parsley, oregano, garlic powder, sea salt, and black pepper.
Drizzle the herb and oil mixture evenly over the cod and the asparagus, using your hands or a brush to coat all sides of the vegetables.
Thinly slice half of the lemon into rounds and layer them directly on top of the cod fillet to infuse it with citrus notes while baking.
Place the baking sheet in the oven and bake for 12 to 15 minutes, or until the cod is opaque and flakes easily with a fork.
Transfer the roasted asparagus and cod to a plate over a bed of warm cooked quinoa, finishing with a final squeeze of juice from the remaining lemon.