I have many fond memories of this dish from my youth. One of my closest friends lived a few streets away from our restaurant and without fail he would order OK Beef and fried rice every night, which meant we always had time for a quick catch up. Although this recipe was developed in the UK for western tastebuds, it is enjoyed throughout the world and has become a firm favourite on the menu in many Cantonese restaurants.
groundnut oil for deep-frying, plus ½ tbsp
1 egg, beaten
340g (12oz) beef fillet, thinly sliced
100g (1 cup) cornflour (cornstarch)
1 onion, thinly sliced
For the OK sauce
2 tsp light soy sauce
1 tsp Chinese five spice
250ml (1 cup) water
125ml (½ cup) tomato ketchup
4 tbsp brown sauce
100g (½ cup) white or brown sugar
1½ tsp cornflour (cornstarch) mixed with 2 tbsp water
Place all the sauce ingredients (except the cornflour) in a wok and heat gently, stirring until it starts to boil. Lower the heat and simmer for a few minutes. Pour in the cornflour mixture, stirring until thickened, then remove from the heat and set to one side.
Heat enough oil to deep-fry the beef in a large saucepan or wok to 180°C (350°F).
In a large bowl, massage the egg into the beef slices. Tip the cornflour onto a large plate and coat the beef strips a few at a time, making sure each piece is covered and shaking off any excess.
Carefully lower the coated beef in batches into the hot oil and deep-fry for 2–3 minutes, or until the beef is golden brown and crispy. Transfer to a wire rack or a plate lined with kitchen paper to drain.
Heat the ½ tablespoon of oil in a non-stick wok and fry the onion until tender, then add the fried beef and the sauce. Mix thoroughly to coat each piece, then transfer to a serving plate and serve.