Tsukuda is the name of an area of Tokyo which actually used to be an island in the Edo era. The fishermen of Tsukuda-jima would cook small fish in a reduction of soy sauce, which resulted in a very salty dish that would keep for weeks – something extremely useful in the days before refrigerators!
The version below uses kombu kelp instead of fish, but feel free to replace it with small cooked or dried fish. Or you could add katsuobushi to the kombu tsukudani (on the left in the picture above) for okaka kombu (on the right in the picture above), another yummy variation.
If you find the taste a little strong, remember that it’s more of a condiment than a dish on its own – it goes great over a bowl of Japanese rice! The version that’s made with nori instead of kombu is actually a paste sold in jars at the supermarket, not unlike the British Marmite or Australian Vegemite!
Kombu Tsukudani and Okaka Kombu
- 60 g second-use kombu i.e. kombu that’s already been used to make dashi
- 5 g water just enough to cover the kombu
- 5 g katsuobushi if making okaka kombu
- 60 mL soy sauce
- 2 tsp rice vinegar
- Cut the kombu into 2cm squares.
- Put all the ingredients (except the katsuobushi) in a saucepan and cook for 30 minutes over medium-low, until the liquid has almost completely evaporated.
- If making okaka kombu, grind the katsuobushi into almost powder consistency, then mix in with the kombu tsukudani.