Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper for easy cleanup.
Pat the cod fillets completely dry with paper towels to ensure the herb rub adheres and the fish roasts rather than steams.
Trim the tough, woody ends from the asparagus spears and arrange them on one side of the prepared baking sheet.
In a small glass bowl, whisk together the extra virgin olive oil, lemon juice, lemon zest, garlic powder, dried oregano, sea salt, and black pepper until well combined.
Place the cod fillets on the other side of the baking sheet and generously brush the lemon-herb mixture over the fish and the asparagus.
Toss the asparagus spears gently with tongs to ensure they are evenly coated in the oil and seasonings.
Roast in the center of the oven for 12 to 15 minutes, depending on the thickness of the fish, until it is opaque and flakes easily with a fork.
While the fish is roasting, fluff your pre-cooked quinoa in a small saucepan or bowl and warm it through if necessary.
Portion the quinoa onto plates and top with the roasted cod and asparagus, finishing with a bright sprinkle of freshly chopped parsley.