Cut cabbage lengthwise into quarters. Remove the hard core and cut the cabbage into bite-sized pieces.
In a large bowl, combine cabbage, water and salt. Toss to combine and set aside. Repeat the mixing every 30 minutes, 3-4 times.
Make the paste
In a pan/pot, combine vegetable stock and glutinous rice flour. Cook on medium heat for 2 minutes, stirring constantly. Once you get a paste, add in sugar and cook for another 2 minutes. Remove from the heat and let cool.
In a food processor, combine porridge, onion, garlic, ginger, miso paste and soy sauce. Blend well. Transfer to a medium bowl and mix in gochugaru.
Mixing everything together
Wash the salted cabbage in water and drain. Repeat this 3-4 times to get rid of the excess salt, otherwise the kimchi will be too salty.
In a large bowl, combine cabbage, radish, carrot and green onions. Add in the chili paste and, using gloves, mix everything together. Make sure every vegetable is well coated in the paste.
Transfer to a clean, air-tight plastic or glass container, making sure to pack it down tightly. Fill it up ¾ of the way, as the kimchi will expand as it ferments.
Keep at room temperature for 24 hours before transferring to the fridge OR let ferment slowly in the fridge for 2 weeks.
Notes
Notes on fermentation:
Keeping the kimchi at room temperature for the first 24 hours helps speed up the fermentation process. By the end of it, you should see bubbles in the liquid. It will continue to ferment in the fridge, becoming more sour.
You can also keep it in the fridge immediately. It will take 2 weeks to ferment.