Preheat your oven to 400°F (200°C) and line a large sheet pan with parchment paper for easy cleanup.
Halve the baby potatoes and trim the woody ends off the asparagus spears to ensure even cooking.
Place the chicken breast, potatoes, and asparagus on the sheet pan, spreading them out into a single layer.
In a small bowl, whisk together the olive oil, minced garlic, dried oregano, sea salt, and black pepper.
Drizzle the herb oil over the chicken and vegetables, tossing well to coat every piece thoroughly.
Squeeze the juice of half a lemon over the entire tray and place the spent lemon hull on the pan for extra aroma.
Roast for 20-25 minutes until the chicken reaches an internal temperature of 165°F and the potatoes are fork-tender.
Let the chicken rest for 5 minutes before slicing to keep it juicy, then serve alongside the roasted vegetables.