Pat the tilapia fillets dry with a paper towel and season both sides evenly with sea salt and black pepper.
Trim the woody ends off the asparagus spears and set aside.
In a small glass bowl, whisk together the Greek yogurt, lemon juice, minced garlic, and chopped fresh dill until the sauce is smooth and combined.
Heat the olive oil in a large non-stick skillet over medium-high heat until shimmering.
Place the tilapia fillets in the skillet and sear for 3 to 4 minutes per side until the exterior is golden brown and the fish flakes easily with a fork.
While the fish cooks, steam the asparagus spears for 4 to 5 minutes until they are tender-crisp and vibrant green.
Warm the pre-cooked quinoa in a small saucepan or microwave until heated through.
Plate the tilapia over the fluffy quinoa, drizzle generously with the lemon-dill sauce, and serve with the steamed asparagus on the side.