To make the dipping sauce, whisk all the ingredients together in a bowl. Set aside until needed. 

To make the fritters, in a bowl mix together the flour, sparkling water, salt, sugar and turmeric and set aside to rest for 10 minutes. Peel the potatoes and cut into julienne strips. Peel and de-vein the tiger prawns and cut in half lengthways. Set aside. 

Now..
Heat the oil in a deep fat fryer to 180°C. Fold the potatoes, prawns, spring onions and coriander through the batter mix. Using your hands, shape them into fritters, making sure you have an even distribution of prawns in each fritter. Lower them into the hot oil and fry until crisp and golden brown. Remove from the fryer and drain well on kitchen paper. 

Serve immediately with the dipping sauce.