Preheat your oven to 400°F (200°C) and line a large sheet pan with parchment paper.
Pat the chicken breast completely dry with a paper towel to ensure the herbs stick and the meat sears beautifully.
In a small bowl, whisk together half of the olive oil, minced garlic, rosemary, thyme, sea salt, and black pepper.
Rub the herb and oil mixture thoroughly over all sides of the chicken breast.
Toss the cubed sweet potato with the remaining olive oil and a pinch of salt directly on the baking sheet.
Place the chicken on the sheet pan alongside the potatoes and roast for 15 minutes.
Add the broccoli florets to the pan, tossing them lightly in the pan juices, and roast for an additional 10 to 12 minutes.
Ensure the chicken has reached an internal temperature of 165°F, then let it rest for 5 minutes before slicing.
Drizzle the entire plate with fresh lemon juice to brighten the flavors before serving.