Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
Trim the woody ends off the asparagus and place the spears on the baking sheet.
Drizzle the asparagus with 0.5 tbsp of olive oil and season with half of the sea salt and black pepper.
Roast the asparagus for 12-15 minutes until tender and slightly charred at the tips.
While asparagus roasts, season the chicken breast on both sides with the remaining sea salt, black pepper, and dried oregano.
Heat the remaining 0.5 tbsp of olive oil in a stainless steel or cast iron skillet over medium-high heat.
Place the chicken in the skillet and sear for 6-7 minutes per side, or until the internal temperature reaches 165°F.
Add the minced garlic to the skillet during the last 60 seconds of cooking to aromatically toast without burning.
Plate the chicken over the warm cooked quinoa alongside the roasted asparagus.
Finish the dish with a fresh squeeze of lemon juice over the chicken and vegetables before serving.