1) Add the cabbage, garlic, spring onion and mushrooms to a blender and blend well.
2) Pour the olive oil in a non-stick pan and place it over medium heat until the oil is hot. Then add the cabbage mixture. Fry the mixture for a couple of minutes until it starts to turn a little golden brown.
3) Take the pan off the heat and let the mixture cool down. Then add the remaining ingredients and stir well. 4) You can start assembling the gyozas now.