
Peel and cut the potatoes into thick chips. Rinse under cold water to remove excess starch. Parboil in salted water for 5 to 7 minutes until just tender. Drain and cool completely in the fridge or freezer. Fry once at 175°C until golden. Set aside on paper towel and season with chicken salt.
In a large bowl, whisk together the self-raising flour, cornflour, salt, chicken powder, custard powder and baking powder. Gradually add the cold sparkling water or beer, whisking until smooth and thick like pancake batter. Add a few ice cubes to keep the batter cold.
Pat the hoki fillets dry, season with salt, pepper, and a pinch of YumYum seasoning. Lightly dust with plain flour to help the batter stick. Dip each fillet into the batter, let the excess drip off, then fry in hot oil at 180°C for 5 to 6 minutes until golden and crisp. Drain on a wire rack or paper towel.