400gwhite fish e.g. hake, haddock, cod, or a mixture(approx. 14 oz.)
½a medium onion
25gmedium matza meal(approx. 3 tbsp)
Pinchof salt and pepper
Approx. 500ml (approx. 2¼ cups) vegetable oil for frying
Finely chop the fish in the food processor. Remove from the bowl and set aside.
Peel and chop the onion, then put in the food processor with the egg and pulse until well combined and almost liquid.
Return the fish to the food processor with the onion/egg mixture, add the matza meal and seasoning, and pulse until everything is just combined. Tip the mixture into a bowl or other container, cover, and refrigerate for at least 30 minutes and up to 24 hours.
When you're ready to fry
Fill a small saucepan with oil to a depth of 2-3cm (approx. 1 inch). Place on a medium flame and heat to 190°C (375°F). Use a food thermometer to measure the temperature of the oil.
While the oil is heating, divide the fish mixture into 18 pieces, and roll each into a ball - this is most easily done with wet hands. Place the balls on a plate or chopping board ready for frying.
Once the oil is the correct temperature, use a slotted spoon to carefully immerse 4-5 fish balls, one at a time, into the oil. The oil will bubble up immediately but should calm down quite quickly.
Don't be tempted to cook more than 4 or 5 fish balls at a time! The oil temperature will drop when you add them to the pan, and too many will lower the temperature too much, meaning that they won't cook properly and will absorb oil and taste greasy.
Fry the fish balls, turning regularly, for about 5-6 minutes until a dark golden brown all over. Carefully remove from the pan using a slotted spoon, and drain on absorbent kitchen paper.
Repeat with the remaining balls until they are all cooked.
Use your thermometer to keep checking the oil temperature as the fish balls cook. If it goes above 190°C (375°F), turn down the heat, otherwise the fish balls will brown too quickly and may still be uncooked in the centre.