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 tough, woody ends off the asparagus spears.
In a small mixing bowl, whisk together the extra virgin olive oil, fresh lemon juice, lemon zest, minced garlic, and finely chopped rosemary.
Place the chicken breast, halved potatoes, and asparagus on the prepared sheet pan in a single layer.
Drizzle the lemon-herb dressing over the chicken and vegetables, tossing them gently to ensure everything is well-coated.
Sprinkle the sea salt and black pepper evenly across the entire pan.
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 to keep it juicy, then serve immediately with the roasted vegetables.