To preserve the napa cabbage
Place the cabbage and salt in a bowl and mix well, press down with a plate. Cover and leave to infuse at room temperature for approx. 48 hrs. Rinse the cabbage in cold water, drain well.
To ferment the napa cabbage
Using a food processor, puree the chillies with all the other ingredients to form a smooth paste. Combine the paste with the napa cabbage and mix well, fill to the rim of the warmed, sterilized jar, press down well and seal tightly. Leave to infuse at room temperature for approx. 24 hrs.