I wanted to make Kangkung sotong for a long time, but I had difficulty finding pre-soaked cuttlefish in the local market. I read an article about how alkali/alkaline water was made from the wood ashes in old time.
Since I have ashes in my Charcoal BBQ grill and some dried cuttlefish, I decided to create alkaline water and soak the cuttlefish the old fashioned way.
1/2 cup of wood ashes
2-3 litres of filtered/drinking water
1 piece of dried cuttlefish
1/2 杯的 炭灰/木灰
1 只 鱿鱼干
2. Wash and clean dried cuttlefish, soak in clean water for 1-2 hours if you wish. Place cuttlefish into wood ash water. Soak for 24 hours.
3. Rinse and clean the soaked cuttlefish thoroughly and use it as you wish.
Note：I find the cuttlefish soaked this way is still a little chewy after preparation, I may try next time with alkali.