The key to authentic miso soup is stock, or dashi. It’s what differentiates that sickly, salty, just-add-water abomination found in too many downmarket chain restaurants and the rich, multi-dimensional bowl of heaven that is real miso soup.
Dashi is made by bringing pure cold water up to a simmer with a few pieces of sea kelp, known as konbu. The deep, subtle flavour of konbu is the backbone of miso soup, an unmistakable note of endless sea water and oceanic flora.
A handful of smoked skipjack tuna flakes, commonly known as bonito, is added at the end which infuses the stock with a wonderful smoky, earthy aroma. Bonito is traditionally bought in wood-like blocks, and shaved using a special box planer called a kezuri. Make sure not to boil your bonito flakes, which will result in bitter stock.
Once you have your dashi, and indeed it can be used for countless Japanese dishes, miso soup is just a mere step away. Quality white miso paste, made from fermented soybeans, is whisked into the hot stock and sake is added for yet another level of flavour. Various extra ingredients can then be added into the diner’s bowl according to personal preference; at Bincho we like to use tofu, wakame seaweed, freshly-cut spring onions and shonai fu, a kind of wheatflour bread garnish.
Miso soup made from scratch should have several complimentary layers of subtle flavour that is nigh on impossible to replicate using the instant powered stuff, and once you taste the real deal you won’t want to settle for second best ever again.