Get the Recipe
A few weeks ago I picked up some pork katsu for lunch, only to return to the office and find a vacant space where the that thick sweet and salty tonkatsu sauce should have been. As I tried to down the rather dry and flavorless katsu, I was forced to dig deep into the bowels of my desk to find what must have been a two-year old McDonalds ketchup packet—to inject some sort of sauciness into my fried pork. It was at this point that I vowed never go without my tonkatsu sauce ever again and decided to learn how to make it.
For what tastes like a rather complex sauce, it's very simple to put together. Although eaten alongside Japanese breaded and fried cutlets, the origins are actually British, with tonkatsu sauce being a sweeter and thicker variation of Worcestershire.
A quick mix of ketchup and Worcestershire gets you most of the way there. I added some soy sauce for extra salt, sugar and mirin for more sweetness, and mustard and garlic powder to add complexity. The end result was the exact sauce I was missing that sad day I was forced into using an inferior product to go with my crispy golden katsu.