Put the ingredients into a pot and mix well with a wooden spoon until it thickens, about 5 minutes.
If you can obtain it, I recommend using this red miso.
Story Behind this Recipe
My friend from Nagoya taught me this recipe. Jumbo Chicken Deep-Fried Cutlets Recipe ID: 611462. Basic Tonkatsu Recipe ID: 1710959. Pork Filet Cutlets Recipe ID: 1729876.
Stir it constantly with a wooden spoon so that it doesn't burn. Adjust the amount of sugar to suit your tastes. If making it in the microwave, keep your eye on it and microwave for about 2-2 1/2 minutes. It's very convenient to prepare a lot of this and keep it stocked as it can be used in various dishes.