Preheat your oven to 400°F (200°C) and line a large sheet pan with parchment paper for easy cleanup.
Mince the garlic clove and zest the surface of the half lemon into a small mixing bowl.
Whisk the extra virgin olive oil, minced garlic, lemon zest, dried rosemary, dried thyme, sea salt, and black pepper together until well combined.
Place the chicken breast on one side of the prepared sheet pan and the trimmed asparagus spears on the other side.
Drizzle the lemon-herb oil mixture over the chicken and asparagus, using your hands or a brush to ensure the chicken is fully coated and the asparagus is tossed evenly.
Slice the remaining lemon half into thin rounds and layer them directly on top of the chicken and asparagus for extra flavor infusion.
Roast in the center of the oven for 18 to 22 minutes, or until the chicken reaches an internal temperature of 165°F and the asparagus is tender and slightly charred.
Remove from the oven and let the chicken rest for 5 minutes before slicing to keep it juicy, then serve immediately alongside the roasted asparagus.