For the marinade, mix in the dijon mustard, lemon juice, vinegar, garlic and salt and set aside

In a ziplock bag, add the chicken and onion and mix to combine. Then, add in the marinade and mix in the bag. Making sure all pieces are equally coated

Let the chicken marinate for 4 hours to overnight (the longer the better)

In a heavy skillet, heat 2 tbls of vegetable oil and brown the chicken pieces on both sides and set aside.

Add the marinade with the onions onto the skillet and sauté for about 5 minutes until the onions caramalise

Cooking in the skillet: move the onions to the side and arrange the chicken at the bottom of the skillet. Then chuck the onions ontop of the chicken. Add in the chicken broth and cover the skillet. Allow the chicken to simmer and cook for 45 minutes over low heat. Make sure the liquid doesnt dry up. If it does, add some more chicken broth

Cooking in the oven: arrange the chicken in the bottom of an oven proof dish and pour the onion marinade over the chicken. Add in the broth and cook in a preheated oven (at 180 degrees Celsius) for 45-50 minutes.

Once chicken is cooked through, remove from heat and serve warm with plain white rice