Preheat your oven to 400°F (200°C).
Pat the chicken breast dry with a paper towel to ensure a crispy sear, then season both sides evenly with dried oregano, garlic powder, sea salt, and black pepper.
Heat 0.5 tablespoon of olive oil in a medium oven-safe skillet over medium-high heat.
Place the chicken in the skillet and sear for 3-4 minutes until a golden-brown crust forms, then flip the chicken.
While the chicken sears, trim the woody ends off the asparagus and toss the spears with the remaining 0.25 tablespoon of olive oil and a pinch of salt on a small baking sheet.
Transfer the skillet with the chicken and the baking sheet with the asparagus into the oven.
Roast for 10-12 minutes, or until the chicken reaches an internal temperature of 165°F and the asparagus is crisp-tender.
Remove from the oven and immediately drizzle the fresh lemon juice over the chicken breast while it rests.
Serve the chicken and roasted asparagus over the warm, fluffy cooked quinoa.