OPTIONAL (see notes): When the chicken skewers are cooked, place them in a heatproof bowl/oven dish. Take a bowl and add small amount of butter (about 1 tbsp) or oil. In a naked flame, burn a magic coal for a few minutes. Turn off the flame and put the magic coal in the small bowl with butter (you will notice a smoke coming from it) and then cover with aluminum foil. Let it stay covered for 10 minutes.