Choose a mason jar that is the appropriate size to fit the sliced leek. I used a 16 oz wide mouth style mason jar. Place the mason jar on your kitchen scale and press tare to zero out the weight of the jar.
Fit the sliced leek into the mason jar and pour in enough water to cover the leeks. Take note of the total weight in grams of the leeks and water combined. To determine the amount of salt you need to add in grams, multiply that number by .02.
For example If the weight of the leeks and water combined is 800 grams then you will multiply 800 by .02 and get 16. I would add 16 grams of salt to my jar.
Tare the scale again and add the amount of salt in grams that you determined in the above step. Put on the lid and shake well to dissolve the salt.
It’s very important to keep the leeks submerged. To do this you can use fermentation weights, pinch bowls, small mason jar or a plastic sandwich bag filled with a little water. (See photos for examples.)
Leave your ferment at room temperature away from sunlight for 4-7 days. Check it once a day to make sure the leeks are submerged. Open the lid slightly on a daily basis to prevent pressure from building up in the jar. Close it again tightly.
Once your fermented leeks have reached the desired flavour, place the jar in the fridge. This will halt the fermentation process. Your fermented leeks will now keep for a very long time. Enjoy!