Preheat your oven to 400°F (200°C) and line a large sheet pan with parchment paper for easy cleanup.
Wash and halve the baby potatoes, and trim the woody ends off the asparagus spears.
Mince the garlic clove and combine it in a small bowl with the olive oil, lemon juice, lemon zest, dried oregano, sea salt, and black pepper.
Place the chicken breast, halved potatoes, and asparagus on the prepared sheet pan.
Drizzle the lemon-herb oil mixture over the chicken and vegetables, tossing them gently to ensure everything is evenly coated.
Spread the ingredients into a single layer, ensuring the chicken has enough space to roast properly.
Bake for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F and the potatoes are fork-tender.
Remove from the oven and let the chicken rest for 5 minutes before serving to keep it juicy.