Make the sauce. Mix together the mustard, ketchup, worcestershire sauce and soy sauce. Put aside.
Slice each chicken breast in half horizontally with a really sharp knife, then cut each in half width-ways. Season the chicken with salt and pepper on both sides.
Spread the panko breadcrumbs out on a plate and whisk the egg in a dish.
Dip each piece of chicken in the egg and then in the breadcrumbs until it is totally covered in the crumbs. Shake then dip in the egg and crumbs a second time. Place the crumbed chicken pieces on a large plate.
At this point, put your rice in to boil or steam while the chicken is cooking.
Pour enough oil into a frying pan (skillet) to barely cover the bottom and heat it up. When it is hot enough (test by dropping a few breadcrumbs into it and If it sizzles energetically, it's ready!), place a few pieces of the crumbed chicken at a time into the pan. Fry for about 3 minutes on each side or until golden brown.
Drain any excess oil from the chicken on paper towels, then slice each piece of chicken width-ways into strips about 1 inch thick.
Serve immediately on top of your cooked rice. Drizzle a little of the tonkatsu sauce over the top of the chicken and around the rice. Serve extra on the side for dipping!
Double coating the chicken in breadcrumbs makes sure it's nice and crispy. Don't be tempted to overcook it. A few minutes on each side should be long enough for crispy, moist chicken.
Pan fry or air fry?
If you have an air fryer, this recipe is ideal for it. Spray your breaded chicken all over with a light coating of oil, then 'fry' for about 5 minutes on each side.
Sauce
If you like use store bought sauce to make this recipe even easier.
How to serve
Chicken katsu is usually served over rice and with tonkatsu sauce drizzled over. If you like you can serve some fresh crunchy lettuce leaves on the side.I sometimes serve a fresh vegetable or some stir fried vegetables on the side too. Delicious!