Preheat your oven to 400°F and line a large baking sheet with parchment paper.
Place the halved baby potatoes on the baking sheet, drizzle with half of the olive oil and a pinch of the salt and pepper, then roast for 10 minutes.
While potatoes roast, whisk together the remaining olive oil, lemon juice, lemon zest, oregano, and garlic powder in a small bowl.
Pat the chicken breast dry with a paper towel and coat it evenly with the lemon-herb marinade.
Remove the pan from the oven, move the potatoes to one side, and place the chicken breast, asparagus, and cherry tomatoes on the other side.
Sprinkle the remaining salt and pepper over the vegetables.
Return the pan to the oven and roast for 15 to 20 minutes, or until the chicken reaches an internal temperature of 165°F.
Let the chicken rest for 5 minutes before slicing to keep it moist and tender.