Dashi stock
The clear, savoury Japanese stock made from kombu seaweed and bonito flakes, in under an hour with only three ingredients.
Make this once, then cook it into 18 different dishes.
- Time50 min
- LevelEasy
- Costabout £0.07 a head
- Makesabout 1.3 litres, enough for 2 or 3 soups for 4 people
Cost is worked out from Aldi and Tesco shelf prices in October 2026. Your shop and brands will differ.
Ingredients
Tick what you need to buy. It goes on your shopping list.
Method
- 1
Wipe the kombu with a damp cloth. Do not rinse off the white powder on the surface, because it carries flavour. Make a few cuts along its edge to release more taste.
- 2
Put the kombu in a saucepan with the cold water and leave for 30 minutes. The soak extracts a gentle, clean umami.
30 min - 3
Heat the pan over a medium heat. When small bubbles appear around the edge, after about 10 minutes and just before it boils, lift out the kombu. If it boils, it turns slimy and bitter.
10 min - 4
Bring the water to a brief boil, then switch off the heat. Add the bonito flakes in one go and let them sink without stirring, for 2 minutes.
2 min - 5
Strain through a fine sieve lined with a sheet of kitchen paper. Do not squeeze the flakes, which makes the dashi cloudy and fishy.
- 6
Use straight away, or cool within 90 minutes. You should have about 1.3 litres.
About dashi stock
Dashi stock is a clear, light Japanese stock made by gently steeping dried kelp (kombu) and shaved dried bonito (katsuobushi) in water. It is the base of miso soup, noodle broths, simmered dishes, savoury egg custards and many sauces.
It tastes savoury, faintly smoky and full of umami, without any heaviness. The kombu gives a clean, rounded depth, and the bonito adds a fragrant, smoky edge. Because it is made in minutes and never boiled for long, it is gentle and fresh rather than concentrated.
This is the classic awase dashi, made with both kombu and bonito. One batch makes about 1.3 litres, enough for two or three soups for four people. A vegan version using dried shiitake mushrooms is in the tips.
Tips
- Never boil the kombu. Remove it just before the water boils, or the stock turns slimy and bitter.
- Do not press the bonito flakes in the sieve. Gentle draining gives a clean, clear stock.
- For a vegan dashi, soak 20 g kombu and 4 dried shiitake mushrooms in the cold water overnight, then heat as above and skip the bonito.
- Reuse the spent kombu and bonito to make a weaker second dashi (niban dashi) for miso soup, simmered for 10 minutes in fresh water.
- Use soft water if you can. Hard water can pull less flavour from the kombu.
Storing and freezing
Use within 2 days in the fridge, as dashi spoils quickly. Cool within 90 minutes and keep chilled, or freeze in ice cube trays or portions for up to 2 months. Heat until steaming hot before use.
Dishes you can make with dashi stock
Buta no Kakuni (Japanese Braised Pork Belly)
GFDFEFButadon (Japanese Pork and Cabbage Rice Bowl)
DFNFKaisen Kare (Japanese Seafood Curry)
GFDFEFKare Ramen (Japanese Curry Ramen)
DFNFKitsune Udon (Udon with Sweet Fried Tofu)
DFEFNFSalmon Ochazuke (Japanese Rice in Dashi Tea Broth)
GFDFEFChikuzenni (Japanese Braised Chicken and Vegetables)
GFDFEFOden (Japanese Winter Hotpot with Daikon and Eggs)
DFNFShabu Shabu (Japanese Beef Hotpot at the Table)
GFDFEFNasu no Agebitashi (Fried Aubergine in Dashi)
GFDFEFAsari no Osuimono (Clear Clam Soup)
GFDFEFKabocha no Nimono (Japanese Simmered Squash)
GFDFEFQuestions
Is dashi vegan?
Not this version, because bonito flakes are dried fish. For vegan dashi, use kombu with dried shiitake mushrooms and skip the bonito. It tastes earthier but still very savoury.
Is dashi gluten free?
Yes. Homemade dashi from kombu, bonito and water is gluten free, dairy free, egg free and nut free. Instant dashi powder often contains wheat or soy sauce, so check the label if you use it.
Where do I buy kombu and bonito flakes?
In Asian supermarkets, larger supermarkets in the world foods aisle, and online. Kombu is sold as dried sheets, and katsuobushi comes in small bags of shavings. Both keep for months in a cupboard.
Can I use dashi powder instead?
Yes, as a shortcut. Follow the packet to make up the stock. Many powders contain salt, MSG and sometimes wheat, so the flavour is stronger and you need less seasoning.
How do I use dashi?
Use it for miso soup, udon and soba broths, chawanmushi, simmered vegetables or tofu, and in sauces. Season it lightly with tamari or miso, because it carries only gentle flavour on its own.
More base recipes
Double check before you cook. Recipes can contain mistakes. Any diet labels come from the ingredients as written in this recipe and are a guide, not a guarantee. Always check every ingredient and the packet label for allergens and cross contamination, and ask your doctor or dietitian what is right for you, especially with coeliac disease, diabetes or a serious allergy. This is not medical advice.