Marinate the chicken with the egg, cornflour and ginger and garlic paste. I did not add salt as the soy sauce adds enough salt to the dish, however you can taste once its cooked and add more salt if required. Refrigerate the chicken for half an hour or you can fry it immediately if you don't have time
Heat oil and fry the chicken in small batches. Set aside
Heat 2 tablespoon oil and sauté the onion, white part of spring onion, chilli and pepper for about a minute. Reserve the green part of the spring onion for later
In a bowl mix soy sauce, chilli sauce, vinegar and tomato paste (if using) together. Add this to the onion mix together with the fried chicken. Heat through
Add more salt if required. Garnish with the spring onion. Serve immediately as desired
Notes
If you add the tomato paste and you find the sauce too acidic you can add a pinch of sugar