Russian style sauerkraut

Directions

1. Peel and core apples
2. Using a food processor with shredding disk, shred apples and baby carrots. I use those peeled carrots because they are well washed.
3. Add salt and sugar to shredded carrots and apples, and add a tablespoon of kefir as starter culture. Mix it all by hands, squeezing it in the process. (Wash your hands well, wipe with a paper towel: NO CLOTH TOWEL). The mix will give some juice. Set the mix aside.
4. Install a (fine) slicing disk to the food processor. Cut cabbage to pieces to feed to the food processor, discard cores. As you've sliced a bowl full of cabbage, transfer it to a large mixing bowl and add a handful of carrot-apple mix. Mix and squeeze by hands. Squeezing will release a bit more juice. Transfer to the stock pot. Slice and mix the rest of cabbage like that.
5. Now that all of the mix is in the stock pot, put a china/glass plate face down on it and weigh it with a half-gallon (or 2 liter) jar filled with water. The mix should have enough juice to cover it. Make sure there is at least 1 inch left to the top, so it will not overflow. Cover the pot and the jar with plastic cling film, to prevent contamination.
6. Put the stockpot at room temperature (70F+). If the nights are cold, you may put it to a sink filled with warm water. Twice a day, you need to let the bubbles out: Remove the protective film, set the jar aside and lift the plate off (use fork). Pierce the mix all over it with a chopstick. Put the plate and the jar back, and cover again with plastic.
7. In 2-3 days it will get a pleasant sour smell. After 5-7 days, when it stops bubbling, reload it to glass jars and refrigerate. It will keep fermenting while in the fridge, losing residual sugar and gaining more acid. I let it age in the fridge at least 2 weeks before eating.