Preheat your oven to 400°F (200°C) and line a small baking sheet with parchment paper.
Trim the woody ends off the asparagus and toss the spears with 0.5 tablespoons of olive oil, a pinch of sea salt, and a pinch of black pepper.
Spread the asparagus in a single layer on the baking sheet and roast for 12 to 15 minutes until tender and slightly charred.
While the asparagus roasts, season the chicken breast on both sides with the dried oregano, remaining sea salt, and black pepper.
Heat the remaining 0.5 tablespoons of olive oil in a medium skillet over medium-high heat.
Add the chicken breast to the skillet and sear for 5 to 7 minutes per side, or until the internal temperature reaches 165°F.
During the last minute of cooking, add the minced garlic to the skillet and sauté until fragrant, then pour the lemon juice over the chicken to deglaze the pan.
Remove the chicken from the heat and let it rest for 3 minutes before slicing.
Serve the sliced lemon-garlic chicken and roasted asparagus over the warm, fluffy cooked quinoa, drizzling any remaining pan juices over the top.