Preheat your oven to 400°F (200°C) and line a large sheet pan with parchment paper.
Scrub the white potato and dice into 1-inch cubes, chop the broccoli into florets, and slice the red bell pepper into thick strips.
Mince the garlic cloves and place them in a small bowl with the olive oil, dried oregano, dried thyme, sea salt, and black pepper, whisking to combine.
Place the chicken breast on one side of the sheet pan and spread the potato cubes, broccoli, and bell peppers across the remaining space.
Drizzle the garlic-herb oil mixture over the chicken and the vegetables, using your hands or a brush to ensure everything is evenly coated.
Roast in the oven for 22 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 squeeze the fresh lemon juice over the chicken and vegetables before serving.