Tonkatsu (豚カツ, とんかつ) Sauce is similar to barbecue or Worcestershire sauce, as it has a sweet yet tangy flavor. It is a sauce made to serve primarily with tonkatsu, or breaded pork cutlets, but can be used with a variety of dishes.
Tonkatsu sauce might be hard to find unless you go to an Asian grocery store, but it can be bought online.
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