400g (14 oz) thin strips of beef (e.g. rump, chuck or flank)
½ cup corn flour (cornstarch)
vegetable oil for deep frying, plus 2 extra tablespoons for stir-frying
1 onion, sliced
1 capsicum (bell pepper), deseeded and cut into small chunks
1 tsp sesame seeds
2 tbsp finely sliced spring onion (scallions)
Marinade:
1 tbsp soy sauce
1 garlic clove, finely grated
Stir-fry sauce:
3 tbsp soy sauce
1 tsp dark sweet soy sauce
1/3 cup ketchup
2 tbsp Chinese Chinkiang Black Vinegar*
¼ tsp chilli flakes



