Add tzatziki ingredients to the bowl, mix well, cover, and refrigerate
In another bowl whisk together all ingredients for the tahini, set aside
In a larger bowl add all the chicken marinade ingredients, mix well and set aside.
Flatten each chicken thigh slightly by placing it on a work surface, covering it with cling film and bashing it with a rolling pin or heavy saucepan. Mix the pounded chicken into the marinade well. Marinate preferably overnight but at least 2 hours in the refrigerator.
If using a rotisserie BBQ then thread chicken pieces onto the middle of the rotisserie attachment rotating each one 90° and packing them close together. If using the oven pre-heat oven to 200°C, cut off the end of the onion to make it sit flat, remove peel and place on an oven tray. Stick the skewer vertically into the onion so it is standing up. Thread the chicken thigh pieces onto the skewer so they lay directly on top of the onion, which is used as a base, keep threading rotating each one 90° and packing them close together
Cook on the rotisserie or in the oven for about 1.5 hours or until the internal temperature reaches 75°C.
Carve off slices of the chicken and serve hot in flat bread with the tahini sauce, tzatziki sauce, chilli sauce and all the accompaniments