Whisk together all of the marinade ingredients.
Place the chicken in a large Ziploc bag and cover it with the marinade.
Refrigerate for a few hours(3-6), turning and massaging marinade into chicken.
Preheat oven to 425°F.
Line rimmed baking sheet with foil and brush it with 1 T. of olive oil.
Add onions to Ziploc bag with chicken and seal. Toss and massage contents again to coat onions,
Spread chicken and onions in pan and bake for 30 minutes, turning chicken every 10 minutes. Broil for about 3 minutes at the end to help crisp it up or use convection setting for about 5 minutes, watching throughout the process.
Remove from the oven and allow chicken to rest a few minutes before slicing for serving. Garnish with chopped parsley.