Preheat oven to 400°F and line a large sheet pan with parchment paper.
Dice the sweet potato into 1/2-inch cubes and cut the chicken breast into bite-sized pieces.
In a small bowl, whisk together the olive oil, lemon juice, lemon zest, minced garlic, oregano, salt, and pepper.
Place the chicken, sweet potato, broccoli, and sliced bell peppers on the prepared sheet pan.
Drizzle the lemon-herb mixture over the ingredients and toss thoroughly to ensure everything is evenly coated.
Spread the mixture into a single layer, ensuring the chicken and vegetables are not overcrowded.
Roast for 20-25 minutes, or until the chicken is cooked through and the sweet potatoes are fork-tender.
Divide into meal prep containers and store in the refrigerator for up to 4 days for a convenient lunch.