Nanban — "southern barbarian" — was the Japanese term for the Portuguese and Spanish traders of the 16th century. Nanban-zuke reflects the Portuguese escabeche (frying and pickling in vinegar) adapted to Japanese ingredients and flavour sensibility. Like katsu, it represents a foreign technique absorbed and completely transformed into Japanese cooking.
Small fish (smelt, whitebait, or sardines) fried until crisp and then immediately marinated in a sweet-sour-salty sauce of rice vinegar, soy, mirin, and dashi with julienned vegetables and chilli. The hot fish marinate as they cool, absorbing the sharp-sweet liquid through their just-fried, porous surfaces. The result is simultaneously crisp and pickled — the vinegar's acid working against the oil's richness to produce a balanced, complex preparation that keeps for days and improves as it does.
Tsuji