Preheat oven to 400°F (200°C) and line a large sheet pan with parchment paper for easy cleanup.
Dice the chicken breast, sweet potato, and bell pepper into uniform bite-sized pieces, then chop the broccoli into small florets.
In a small bowl, whisk together the olive oil, lemon juice, minced garlic, dried oregano, sea salt, and black pepper.
Place the chicken and vegetables on the prepared sheet pan and pour the lemon-herb dressing over them, tossing well to ensure every piece is coated.
Spread the mixture into a single layer, ensuring the chicken pieces are not overlapping to achieve even browning.
Roast for 20-25 minutes, or until the chicken is cooked through and the sweet potatoes are fork-tender.
Divide the meal into prep containers and garnish with extra lemon wedges if desired.