Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper for easy cleanup.
Trim the tough, woody ends off the asparagus spears and arrange them in a single layer on one side of the prepared baking sheet.
Pat the cod fillets dry with a paper towel to ensure a better texture, then place them on the other side of the baking sheet.
In a small glass jar or bowl, whisk together the olive oil, lemon juice, lemon zest, dried oregano, garlic powder, sea salt, and black pepper.
Drizzle the lemon-herb emulsion evenly over both the cod fillets and the asparagus spears, tossing the asparagus slightly to coat.
Roast in the oven for 12 to 15 minutes, or until the cod is opaque and flakes easily with a fork and the asparagus is vibrant and tender.
Divide the warm cooked quinoa between plates, top with the roasted cod and asparagus, and garnish with a sprinkle of fresh parsley.