*Any frozen seafood should be defrosted first before being prepared.
Individually rinse the fish, squid and prawns in cold water and pat dry them separately with paper towel. Cut the fish and squid into a few chunks. (No need to cut the prawns) Put all of them into a food processor and grind them finely. (It takes between 30 sec to 1 min). Move the ground seafood batch into a large mixing bowl.
Separately pat dry all the vegetables with paper towel. Put them into a food processor and grind them. (It takes about 10 sec). Move the ground vegetables batch into the large mixing bowl.
Add the rest of the ingredients (egg white, rice wine, sugar, salt, starch and flour) into the bowl and mix them well. Prepare two large flat plates and lay down some waxed paper (e.g. baking paper) on top. Scoop out 1 Tbsp of the fish cake mixture and take it out using another spoon (tea spoon size is good). Place the fish cake ball on to the waxed paper. Repeat this for the rest of the mixture.
Put the vegetable oil into a deep sauce pan and bring it to boil on high heat until it bubbles (about 5 mins). Reduce the heat to medium or medium low. Add some fish cake balls (no more than 6 balls at one time, it will depend on the size of your sauce pan) using tongs into a pan and deep fry them until they are cooked (usually for 2 to 3 mins). Outside of the fish ball is "very lightly" crispy and inner is very soft.
Take the fried fish cake balls out using a strainer. Move them onto some waxed baking paper or paper towel to soak up some oil. Cool down for 5 to 10 mins.
Serve & enjoy! (You can serve it with some tomato sauce/ketchup/mustard sauce). Or you can use this as an ingredient for other fish cake dishes (e.g. fish cake stir fry).