Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Wash the gold potato and dice it into uniform 1-inch cubes; trim the ends of the green beans.
Mince the garlic cloves and finely chop the fresh rosemary and thyme leaves.
In a medium bowl, toss the potato cubes and green beans with half of the olive oil, half of the salt, and half of the pepper.
Pat the chicken breast dry with a paper towel and rub it with the remaining olive oil, minced garlic, rosemary, thyme, salt, and pepper.
Spread the potatoes and green beans onto one side of the prepared baking sheet and place the chicken breast on the other side.
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 golden and tender.
Remove from the oven and drizzle the fresh lemon juice over the chicken and vegetables before serving.