In a mixing bowl combine the pomegranate molasses, garlic, sumac, tomato puree, chilli flakes and sriracha. Add the chicken thighs and coat in the marinade. Cover the dish and pop into the fridge for an hour to let the flavours infuse.
Pre-heat the oven to 190ºC.
Cook the thighs for 30 minutes until the chicken is cooked through and no pinkness remains.
Serve with your choice of accompaniment.