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 tough, woody ends off the asparagus spears.
In a small mixing bowl, whisk together the extra virgin olive oil, lemon juice, lemon zest, minced garlic, dried rosemary, sea salt, and black pepper.
Place the chicken breast, halved potatoes, and trimmed asparagus onto the prepared baking sheet.
Pour the lemon-herb dressing over the ingredients, using your hands or tongs to toss the vegetables and coat the chicken thoroughly.
Spread everything out into a single layer, ensuring the chicken is not covered by the vegetables to allow for even browning.
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 potatoes are fork-tender and golden.
Remove from the oven and let the chicken rest for 5 minutes before slicing it into strips.
Plate the sliced chicken alongside the roasted asparagus and potatoes, drizzling any remaining juices from the pan over the top.