Brine your chicken (optional). Brine your chicken overnight by placing it in a closed container or bag filled with water, salt, and pepper to taste. I love the extra flavor and tenderness of brining the night before, or two days before, it really makes all the difference!
Pound your chicken. When you're ready to assemble, remove from the wet brine and pat dry. If you are using skinless chicken breasts, start by beating your chicken and season with salt and pepper. I like to place the chicken in a plastic bag and pound with a tenderizer/mallot or heavy pan to make the chicken thin.
Prep your slaw and katsu sauce. Before you start breading your chicken, make your cabbage slaw and prepare your Tonkatsu sauce by mixing ketchup, Worcestershire sauce, sesame seeds, soy sauce, and garlic powder. Set aside.
To make your cabbage salad, thinly slice cabbage and toss with green cabbage, green onions, mayo (preferably Kewpie Japanese mayo), dijon mustard and salt and pepper to taste. You can also just serve this as raw cabbage and omit making the cabbage salad.
Prep your frying station. Next, get your frying station ready by making a plate or shallow bowls of potato starch, a plate of panko breadcrumbs and a bowl of beaten eggs.
In a deep pot or skillet, heat up vegetable or canola oil (or any neutral oil of choice) Once it’s hot, start to dredge your chicken in potato flour, then the eggs, then the panko, deep fry until evenly cooked and crispy, and golden brown (about 15-20 minutes), until the internal temperature reaches 165 degrees F.
Assemble, slice and serve. Remove the katsu from the oil on a plate lined with paper towels to shake off any excess oil and let rest for 5 minutes, slice into thin slices/strips and serve with your tonkatsu sauce to dip with your chicken and cabbage slaw.