Mix marinade ingredients together, then add chicken. Put in ziplock bag and let marinate several hours or overnight.
Preheat the oven to 425.
Grease a shallow pan. Take the chicken out of the marinade and spread it in a single layer on the pan, and top with the onions (sliced or quartered). If you kept the garlic in larger pieces, fish those out of the marinade and strew them over the chicken. Cook for 45 minutes or more.
Chop up the chicken a bit, if you like, and finish cooking it so it crisps up a bit more.
Serve chicken and onions with pita bread triangles, cucumbers, tomatoes, assorted olives, feta cheese, fresh parsley, pomegranates or grapes, fried eggplant, and yogurt sauce.