Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper for easy cleanup.
Rinse the quinoa under cold water, then combine it with the water in a small saucepan; bring to a boil, reduce to a simmer, cover, and cook for 15 minutes.
In a small mixing bowl, whisk together the miso paste, mirin, honey, grated ginger, and minced garlic until the glaze is smooth and well-combined.
Place the cod fillets and the trimmed asparagus spears on the prepared baking sheet in a single layer.
Brush the miso glaze generously over the top and sides of the cod fillets.
Drizzle the asparagus with the toasted sesame oil and season with the sea salt and black pepper.
Roast in the center of the oven for 12 to 15 minutes, or until the cod is opaque and flakes easily with a fork and the asparagus is tender.
Once the quinoa is cooked, fluff it with a fork and stir in the shelled edamame, allowing the residual heat to warm them through.
Divide the edamame-quinoa mixture between plates, top with the roasted asparagus and miso-glazed cod, and garnish with freshly sliced green onions.