For the dressing,combine all the ingredients and stir to dissolve the sugar.
Add 2 tbsp of cold water and set aside for 5 minutes for the flavours to combine.
Slice fish into 1 cm slices. Combine the flours and salt and lightly dust the fish slices,shaking off any excess.
Heat the oil to 175°C and fry the fish slices for about 2 minutes until crisp. Remove from the oil and drain on a wire rack.
Combine the cucumber,carrot,onion,tomato,Vietnamese mint and pineapple and toss with the dressing.
Add the fish slices,toss again,and serve immediately.
Adam's tip: One of the most important ways we control texture in the kitchen is with our cutting. For a salad like this one,take your time to cut the vegetables as finely as you can. A little extra effort in cutting will make a big difference to the texture when you're eating.