Preheat oven to 400 F. Grease a large baking sheet with oil or line with parchment paper or aluminum foil for easier cleanup.
Add chicken to the pan and bake in the oven for 8 minutes. Toss vegetables and flip chicken, then return to the pan to bake for another 10-12 minutes, or until the chicken is cooked through (depending on how thick your chicken is - I pounded mine to pretty thin pieces so they cooked fast). Drizzle with reserved marinade.