Preheat your oven to 400°F and line a large rimmed baking sheet with parchment paper.
Trim the tough, woody ends off the asparagus and arrange the stalks on one side of the prepared baking sheet.
Pat the cod fillets dry with paper towels and place them on the other side of the baking sheet.
In a small bowl, whisk together the extra virgin olive oil, minced garlic, lemon zest, chopped parsley, dill, sea salt, and black pepper.
Drizzle the herb and oil mixture over both the cod and the asparagus, using a brush or clean hands to ensure the fish is well-coated and the asparagus is tossed evenly.
Slice the remaining lemon into thin rounds and place them directly on top of the cod fillets.
Bake for 12 to 15 minutes, or until the cod is opaque and flakes easily with a fork and the asparagus is tender-crisp.
Transfer the roasted cod and asparagus to a plate and serve immediately over the warm cooked quinoa.