The Origin Story
Dashi is the soul of Japanese cooking. It's the base of miso soup, the foundation of ramen, the invisible hand that ties together washoku — traditional Japanese cuisine. Two ingredients: kombu (dried kelp) and katsuobushi (bonito flakes). That's it. No aromatics, no spices, no fuss. Just pure umami.
I learnt to make dashi from Chef Takeshi Horiuchi at a small ryokan in Kyoto, where he'd been making it the same way every morning for thirty years. He used spring water from the mountains, kombu from Hokkaido, and bonito shaved that morning. He told me: "Dashi is not cooking. Dashi is listening. You listen to the water, you listen to the kombu, you listen to the katsuobushi. They tell you when they are ready."
The technique is deceptively simple, but the timing is everything. Boil the kombu and you get bitterness. Boil the katsuobushi and you get fishiness. Treat them gently, and you get something clean, clear, and profound.
A Note on Tradition
Dashi is classified as one of the five basic stocks of world cuisine, alongside French stock, Chinese stock, Indian stock, and Italian brodo. In Japan, it's foundational — not a dish, but a starting point. Every region has its variations: kombu dashi (vegetarian), niboshi dashi (dried sardines), shiitake dashi (mushrooms). But the classic version — ichiban dashi — is kombu and katsuobushi, and it's what you learn first.
Ingredients
- 1 litreWater (preferably filtered or spring water)
- 10gKombu (dried kelp)Hokkaido kombu is prized — look for thick, dark green pieces
- 20gKatsuobushi (bonito flakes)Freshly shaved if possible, otherwise use quality packed flakes
Method
Wipe the kombu. Gently wipe the kombu with a damp cloth to remove any grit, but don't scrub — the white powder on the surface is flavour, not dirt.
Soak the kombu. Place the kombu in a saucepan with the cold water. Let it soak for at least 30 minutes, or up to overnight in the fridge. This cold soak extracts the umami without bitterness.
Heat gently. Place the pan over medium-low heat and heat slowly. Watch for small bubbles forming on the kombu and around the edges of the pan — this will take about 10 minutes. Do not let it boil. If it boils, the kombu releases bitter compounds.
Remove the kombu. Just before the water comes to a full boil, remove the kombu with tongs and discard (or save for a second, lighter stock). The water should be steaming and just starting to simmer.
Add the katsuobushi. Bring the water to a full boil, then immediately turn off the heat. Add the katsuobushi all at once — it will float, then sink.
Steep for 3 minutes. Let the katsuobushi steep without stirring. After 3 minutes, the flakes will have sunk to the bottom and the stock will be golden and aromatic.
Strain. Strain the dashi through a fine-mesh sieve or cheesecloth into a clean bowl. Don't press or squeeze the flakes — just let gravity do the work. Pressing releases bitterness and cloudiness.
Use immediately or store. Dashi is best used the day it's made. Store in the fridge for up to 3 days, or freeze for up to a month.
Where This Came From
This technique was taught to me by Chef Takeshi Horiuchi at a traditional ryokan (inn) in Kyoto's Arashiyama district. He learnt it from the chef before him, who learnt it from the chef before him — an unbroken line going back decades. Chef Takeshi told me that in Japan, making dashi is one of the first things an apprentice learns, and one of the last things they master.
I've made it with tap water in Melbourne, and it's still good. But when I use filtered water and good-quality kombu and katsuobushi, I can almost taste the Kyoto mountains in it.
