Preheat your oven to 400°F (200°C) and line a large sheet pan with parchment paper.
Halve the baby potatoes and trim the woody ends off the asparagus spears.
In a small bowl, whisk together the olive oil, lemon juice, minced garlic, rosemary, thyme, salt, and pepper to create the marinade.
Place the chicken breast and halved potatoes on the sheet pan, then drizzle with two-thirds of the herb oil mixture, tossing the potatoes to coat.
Roast in the center of the oven for 15 minutes.
Remove the pan, add the asparagus to the empty space, and drizzle the remaining herb oil over the spears.
Return the pan to the oven and roast for an additional 10-12 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 and serving with the roasted vegetables.