bon appetit has an article about the Katsu Sando Boom in their September magazine. Apparently it’s all the rage on the internet. Here is what they had to say about the ingredients and how to put it together.
I guess the traditional Katsu Sando is made with a Japanese milk bread, but you can use a good white bread. If buying a whole loaf use an electric knife for even slices and leave the bread untoasted. You’ll have crispy pork and crunchy cabbage so you need soft bread to give it some balance.
Use a pork loin and marinate it first before frying in a mixture of soy sauce, minced garlic, mirin and toasted black peppercorns.
Crunch is elusive with any sandwich and hot katsu can get soggy fast. But if you coat your meat in panko and fried bread scraps you’ll get the ultimate crackled crust.
Say yes to the cabbage as it will cut through the richness of the fried pork loin and sauces.
Tonkatsu sauce is a given or make your own with Japanese hot mustard, soy sauce, rice vinegar, oyster sauce and dried prunes made smooth in a blender. Add a few swipes of mayo to finish the job. Yum Yum!