Mix the marinade ingredients in a disposable baking dish (the most practical because the process is messy). Add the chicken and mix well. Marinate for a minimum of 5 hours (or overnight) in the refrigerator
Preheat the oven to 400 F (200 C)
Bake for 45 minutes. The entire process up to this point may be completed a day or two ahead and the baked chicken stored in the refrigerator
Before serving, finely slice the chunks of chicken
Fry the onion in oil until golden and remove from the pan
Add the chicken with some of the marinade to the pan. Season and stir-fry for a few minutes, until the edges are golden-brown. Spread the fried onions over the meat and serve