1

Slice the daikon with a very sharp knife, as thinly as possible. Stack the slices into a neat pile and slice again into very thin sticks. Place in a bowl of iced water and chill for about 10 minutes.

2

Meanwhile, slice the fish. Using your sharpest knife, cut the tuna, salmon and halibut, sea bream or swordfish into thin strips. Do this with one motion, starting with the part of the knife's edge closest to the handle, drawing it back towards you in a smooth motion. Avoid sawing the fish or you will spoil the texture that you are aiming for.

3

Sprinkle the vinegar over the cucumber, then arrange it onto 4 serving plates. Drain the daikon and pat dry with kitchen paper. Arrange on the plates with the fish. Serve with the soy sauce, to use as a dipping sauce for the fish.