Preheat your oven to 400°F and line a large sheet pan with parchment paper for easy cleanup.
Dice the red potatoes into half-inch cubes and trim the woody ends off the asparagus spears.
In a small bowl, whisk together the olive oil, lemon juice, minced rosemary, garlic powder, sea salt, and black pepper.
Place the diced potatoes on one side of the sheet pan, drizzle with one-third of the herb oil, and toss to coat.
Roast the potatoes for 12 minutes to give them a head start on becoming perfectly crispy.
Remove the pan from the oven and place the chicken breast in the center, then arrange the asparagus and cherry tomatoes on the remaining side.
Brush the remaining herb oil over the chicken breast and vegetables until everything is well-coated.
Return the pan to the oven and roast for an additional 18 to 20 minutes until the chicken reaches an internal temperature of 165°F and the potatoes are golden brown.
Let the chicken rest for 5 minutes before slicing to ensure it stays juicy and flavorful.