Kimchi is the perfect ferment to start with. The ginger and garlic in the spice paste, along with the sugar in the apple juice, seem to kick-start the fermentation, so it gets going nice and quickly, while the antimicrobial effects of chilli keep it reasonably safe from unwanted visitors. It’s also, importantly, delicious – a little bit of it effortlessly elevates a bowl of rice or noodles, you can treat it as a pickle and put it in a cheese toastie, or just eat it as a snack.
In Korean cuisine, 'kimchi' actually covers a huge variety of different vegetable ferments, some dense and spicy, some clear and brined, but this kind, a ‘red kimchi’ of cabbage is probably the most famous. (A red kimchi contains chilli flakes or paste, a white kimchi does not). This recipe, I should say, is considerably simpler than most – partly to avoid an intimidating shopping list, but mostly because simplicity is best and I like it like that.
Even within traditional recipes, in any case, you’ll find endless variation. Alongside the chilli and ginger some kind of garlic or onion is usually there, whether spring onion, chive, or leek. The fish element might come from dried shrimp or anchovy or even fresh oysters or not, for stricter Buddhists, be present at all; a mix of vegetables, such as shredded carrot and daikon, might be added to the cabbage.