First in a bowl mix the ginger, vinegar, salt and sugar, then add the chopped cucumber into thin slices. Mix well. Then in a large frying pan, heat 1 tbsp sunflower oil, fry the onion, finely chopped, until golden and place in a deep bowl. Add onion to both canned salmon, as you have previously removed the leather or larger bones (if any). Also add mayonnaise, wasabi, milled rice crackers and 1/4 of the liquid from pickled cucumbers. Mix well and shape into 6 balls. Fry them in the remaining sunflower oil until golden. Garnish with pickled cucumbers.