I came across Mizkan Oigatsuo Tsuyu Bonito Soup Base by typing ‘bonito’ into Ocado’s search box; I wanted to buy flakes but this was the only bonito item they stocked and it looked promising.
It’s not cheap at £4.55 a bottle but I assumed that it was super concentrated (like oyster sauce) and would last for months. I was wrong. The bottle tells you to use it within 18 days once opened and suggests that you mix 150ml of soup base with 450ml of water (to serve 2) so you get 3.3 servings out of a 500ml bottle. I was annoyed but then I tasted it and all was forgiven. It has a delicate, savoury flavour that I recognise from dishes I’ve had in Japanese restaurants - the kind of flavour I thought could only be achieved by a skilled chef simmering obscure ingredients for many hours.
All of the information about portion sizes and shelf life is on the Ocado website but I didn’t pay attention and I’m glad because I would have missed out on one of my favourite discoveries in the last few years.
I add thawed frozen udon noodles, spinach and skirt steak to the soup base. The soup, noodles and vegetables come together in the time it takes the steak to cook (4 minutes plus resting time) and because I reduce the amount of soup base I use (125ml with 375ml water) I get four portions out of a bottle.
I’ve found that frozen udon noodles have an irresistibly chewy texture, similar to udon I’ve eaten in restaurants, and I prefer them to the wok-ready noodles that I've been buying for years. I still buy them as they’re cheap, convenient and decent but I always use frozen udon with this soup base.
Using up the soup base within 18 days is no hardship as it’s moreish and I vary the protein and vegetables (salmon, tofu, prawns, broccoli and spring onions all work well).
At the moment Ocado is the only online supermarket that stocks frozen udon and Mizkan’s soup base and as long as they continue to sell them, I’ll keep buying. You can get the soup base from other online retailers but it’s considerably more expensive.
At £4.55 a bottle and using slightly adjusted quantities, Mizkan’s soup base works out at £1.14 per use - 8 glorious bowls of soup in total - and is a speedy, delicious ingredient that satisfies my frequent and insistent cravings for Japanese food.