Combine all ingredients for the filling and season to taste.
Place a spoonful of filling onto a wrapper. Seal the wrapper using the technique you're most comfortable with.
Heat cooking oil over a high heat. Start frying the dumplings until the bottom part is golden brown.
Pour cold water into the pan and cover up to ⅓ of the dumplings. Cover the pan with a lid and cook over a high heat until the water evaporates completely. Fry for another 30 seconds for the dumplings to crisp up.
Mix the ingredients for the sauce together and serve alongside the gyoza.