Mix all the marinade ingredients in a bowl so they are fully combined.
Slash the chicken pieces to the bone and place in the bowl with the marinade, fully coating the pieces. Marinate in the fridge as long as possible, overnight if you can.
Preheat the oven to 180°C.
Slice each of the new potatoes halfway down but not all the way through (hassleback) 3 or 4 times, to pick up the flavours while cooking. Place in a large roasting pan with the pieces of corn, onion and lemon wedges.
Place the marinated chicken in between the vegetables and drizzle over the mustard oil, cumin seeds and a sprinkling of salt.
Place in the hot oven and bake for 30 minutes. Then add the capsicum chunks and cook for an additional 15 to 20 minutes until cooked and the chicken has crisped up.
To serve, sprinkle with coriander, sliced onion and red chilli slices (optional).