Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper for easy cleanup.
Pat the chicken breast completely dry with paper towels to ensure a good sear and trim any excess fat.
In a small mixing bowl, whisk together the olive oil, minced garlic, dried rosemary, dried thyme, sea salt, and black pepper.
Place the chicken breast and the trimmed asparagus spears onto the prepared baking sheet.
Drizzle the herb and garlic oil mixture over both the chicken and the asparagus, using your hands or a brush to coat everything thoroughly.
Slice half of the lemon into thin rounds and arrange them on top of the chicken breast; set the other lemon half aside.
Roast in the center of the oven for 20 to 25 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 squeeze the remaining lemon half over the entire tray before serving warm.