1. First we make the filling : In a bowl, add all ingredients A and mix well. Knead the mixture by hand until getting a sticky texture.
2. Place a spoonful of the mixture in the center of a gyoza wrapper and wet the edge of the wrapper with your fingertip. Make pleats on one side, then fold over and seal to close. Continue with the rest of the gyoza wrappers until you used all filling.
3. Heat 2 tbsp vegetable oil in a large frying pan over medium to high heat. Add several gyozas (how many really depends on your pan size) and cook them until golden brown and crispy on the bottom.
4. Add hot water (about 100ml), cover pan with the lid and let it steam over medium heat for about 2 mins or until all water evaporates. Repeat with the remaining gyoza.
5. In a small bowl, add all the sauce ingredient and mix.