This is easy to make, I used to buy the sour cabbage from the store but they don’t really taste right, maybe they add something else to make it ferment faster so the taste of it is usually way too strong for me.
You will need a big glass jar, some Chinese cabbage or mustard green. The only ingredients adding are water and salt.
Add 2% of salt to the total weight of vegetables (vegetable cleaned and cut in halves or quarters) and let it sit for one to two hours in room temperature until the vegetable is wilted and a lot of water coming out of the vegetable.
Add the vegetable and the water from the vegetables to the big jar, usually the water from vegetable is not enough to cover the vegetable, so you will need to add some more water to the jar. Weigh the water you need then add 2% of salt to the total weight to the water and stir to dissolve the salt, then add it to the jar.
Make sure the water is enough to cover all the vegetable, don’t let any of the vegetable float to the surface. You can use a piece of stone to press down vegetable, if you don’t have one, then get a plastic bag and add some water to it and tie it up tight and put it on top of vegetable.
Seal the jar with the lid and keep it in a cool dark place for 2-3 weeks, it all depends on the weather, if it is warm/hot then it will ferment faster, if it is cold then it may take 4 weeks to become sour. If you use Chinese cabbage the color will go from light greenish yellow and white to beautiful yellow and white when it is ready. If you use mustard green then the color will go from bright green to brownish green like the pictures shown above.
When you think it is sour enough you can take it out and keep them in freeze for up to one month. The taste of it is smooth sour not too strong. I use it to make soup, saute with meat or just saute by itself. Yum!