Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper for easy cleanup.
Finely mince the garlic clove and the fresh rosemary leaves.
Trim the woody ends off the asparagus and place them on one side of the baking sheet along with the cherry tomatoes.
Drizzle the vegetables with half of the olive oil and sprinkle with a pinch of the sea salt and black pepper.
In a small bowl, whisk together the remaining olive oil, lemon juice, lemon zest, minced garlic, and rosemary.
Place the chicken breast on the other side of the baking sheet and rub the lemon-herb mixture thoroughly over both sides.
Season the chicken with the remaining sea salt and black pepper.
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.
Let the chicken rest for 5 minutes before slicing to ensure the juices stay locked in, then serve immediately with the roasted vegetables.