Preheat your oven to 400°F (200°C) and line a large rimmed sheet pan with parchment paper for easy cleanup.
Cut the chicken breast into 1-inch cubes and chop the broccoli, bell pepper, and sweet potato into uniform, bite-sized pieces.
In a small mixing bowl, whisk together the extra virgin olive oil, fresh lemon juice, minced garlic, dried oregano, sea salt, and black pepper.
Place the chicken and all the vegetables onto the prepared sheet pan and pour the lemon-herb dressing over the top.
Toss everything thoroughly with your hands or tongs to ensure every piece is evenly coated in the seasoning.
Spread the mixture into a single layer across the pan, making sure not to overcrowd the ingredients so they roast rather than steam.
Roast in the center of the oven for 20 to 25 minutes, or until the chicken is cooked through and the sweet potatoes are fork-tender.
Remove from the oven and let cool slightly before dividing into airtight containers for your weekly meal prep.