Preheat your oven to 400°F (200°C).
Place the chicken and chopped vegetables on a large baking sheet. Cut everything a similar size so it cooks evenly.
Drizzle with olive oil, then sprinkle on the oregano, salt, and pepper. Toss with your hands until everything is coated.
Spread it all in a single layer. Don't overcrowd the pan, this is the step everyone rushes and regrets.
Roast for 20 to 25 minutes, until the chicken is cooked through and the veggies have tender, slightly crispy edges.
Serve right away on its own, or over quinoa, brown rice, or a light salad.