Remove any tough stalky centre from the cabbage and then finely slice (I use a food processor on fine cut).
Massage 2 tsp of salt into the cabbage with your hands until the cabbage begins to soften.
Put cabbage into a wide topped glass jar, interspersed with 6 -12 juniper berries and press down firmly.
Stir 1 level dessertspoon sea salt into 2 cups of water. Add water to cabbage until it just covers the cabbage (make up more if needed). Press cabbage down again.
I put a small zip-lock bag into the top of the jar and fill with enough of the brine to hold the cabbage under the brine mix. Place lid on top loosely and leave at room or larder temperature for 3 to 14 days.
Once it has fermented to sufficient softness and flavour, place the jar in the fridge, where it will keep for 1 – 2 months (some people are happy to leave it longer; flavours deepen).
To serve, remove as much cabbage as you want from the brine and press out excess liquid. Use the liquid to flavour soups and stews.