Sift flour and bicarbonate of soda into a mixing bowl. Add turmeric powder, salt, pepper and sugar to mix.
Add egg and water mixture, and mix into a smooth batter.
Finally, stir in onion and prawns to combine.
Heat enough oil in a wok over medium heat. Drop a tablespoon of batter into the hot oil and deep-fry the fritters until golden brown.
Dish out and drain on kitchen paper towels.