You're not going to believe how quickly this izakaya-style dish lands on the table. Nor will you believe the speed with which it is devoured. It's all thanks to delicious, ready-to-cook schnitzels (or kastu, if you want to be Japanese about things), and a fast tonkatsu sauce that's whisked up in seconds. It's crisp, it's crunchy, it's nice for next-day lunch-y.
Heat oil in a frypan over medium heat. Add schnitzels and cook, turning halfway, for 8–10 minutes or until cooked through. While schnitzels cooking, continue with step 3.
Drain schnitzels on paper towel and season well with salt and pepper.
Finely slice cabbage. Halve cherry tomatoes. Finely slice spring onion.
Place cabbage, tomato, spring onion and sesame dressing in a bowl with a pinch of salt and pepper and mix to coat.
Place oyster sauce, ketchup, brown sugar and soy sauce in a small bowl and mix to combine.
Slice schnitzels. Divide schnitzel and slaw between plates and drizzle with tonkatsu sauce to serve.