Tonkatsu sauce
Tonkatsu sauce or katsu sauce is a Japanese sauce served with tonkatsu (pork cutlet). It is a thick (viscosity over 2.0 pascal-second, per JAS Standard) Japanese Worcestershire-type sauce. It is similar to the British and Irish brown sauce, and can include a fish sauce, tomatoes, prunes, dates, apples, lemon juice, carrots, onions, and celery among its ingredients.