Finely chop the mixed herbs ( chives are great in here) and mix with the Greek Yoghurt, seasoning and wasabi if using. Chill
Lay out two slices of smoked salmon or trout on a square of cling wrap, approximately 20cm x 20 cm, (8 inx 8in) .Overlap the slices after cutting off the brown membrane running at the top of each slice.
Put a tablespoon of the yoghurt onto each 2 slice package and pull up the plastic bringing all of the sides together. Secure with the top of the cling wrap by twisting to seal together in a round bomb shape. As you finish each one pop it in the fridge to cool and set.
Put the chopped tomato and it's juice into a bowl and add the rinsed chopped capers. The rinsed Spanish onion ( the onion should not be overpowering, use chives if you like), then the parsley lemon juice and olive oil. Mix well and taste for seasoning. Stand.
Put the sugar and vinegar into a saucepan and simmer till the sugar is dissolved. Add the small amount of wasabi and stand till cooled. The wasabi adds a lovely flavour and is not hot and spicy. Pour this mixture over the cucumber ribbons and refridgerate for up to around 3 hours. You can make the syrup ahead and add the cucumbers a little bit before you need them. They go very transparent and soft after this time. They are still lovely but they don't have the same crunch.
Unwrap and serve the Salmon bombs with the salsa and pickled cucmbers and a little extra olive oil