The dry-salting fermentation method used to make sauerkraut works brilliantly on almost any firm vegetable, so you can happily explore beyond the traditional cabbage. I had a couple of carrots and a piece of squash that needed saving, so I turned them into a golden kraut with ginger, turmeric and a little orange zest for brightness. Use whatever you have to hand and let the ingredients lead your creativity.

Fridge raid sauerkraut

Fermenting is an enjoyable way to make the most of a seasonal ingredient or to use up surplus produce. At our restaurant, whenever we had a glut that needed using up, we used to rely on fermentation, because not only did it saves us money in the long term, it also helped us to create imaginative, delicious new products to cook with.

Classic cabbage kraut is, of course, glorious, but there are all manner of alternatives, and some magic combinations. Just get creative, use what you have and eat the rainbow. As with classic sauerkraut, the general rule of thumb is that you need about 3% salt to the total weight of vegetables.

Now, just a few notes on fermentation in general. Keep the jar out of direct sunlight and check on it every day. Give it some love, and a stir, perhaps, and make sure the ingredients are always submerged in the liquid (a fermentation weight will help here, as would any other clean weight). Only use organic unwaxed citrus zest, because conventional citrus tends to be subjected to very high levels of fungicides and pesticides.

Finally, if you’re new to fermenting, maybe consider making two jars: keep one in the fridge and leave the other to ferment on the counter, then taste both over time to teach your tastebuds how the flavour of each develops as it matures. You will need a large sterilised jar with a lid.

Makes 1 x 500g jar

400g mixed hard vegetables (carrot, squash, beetroot, kohlrabi, turnip, radish, celeriac, broccoli stems – any combination you like), all washed and grated or finely sliced
12g sea salt

Optional extras
Finely grated zest of 1 unwaxed organic lemon or ½ orange, to taste
1-3 tsp grated fresh ginger, to taste
1 small piece fresh turmeric, or 1 tsp ground turmeric (this will dye the food yellow)
1-2 tsp caraway, cumin or coriander seeds, whole or ground, to taste

Tip the grated vegetables into a large bowl, scatter over the salt, then add any of the optional extras that you fancy. Mix everything with your hands, and massage firmly for a few minutes, until the vegetables start to soften and release their juices.

Spoon the mixture into a large sterilised jar, press it down tightly, then pour in any brine from the bottom of the bowl and firmly push the vegetables beneath the liquid; if they aren’t fully submerged, top up with a splash of filtered water mixed with a tiny pinch of salt.

Place the lid loosely on top of the jar – this will allow the gases to escape – then leave at room temperature for at least four days, checking regularly until it’s bubbling and the brine tastes lightly acidic. If you prefer a deeper, more complex flavour, keep it fermenting it on the counter for longer. Otherwise, for a milder kraut, seal and put in the fridge, where it will keep for four to six months.