Soak soya chunks in enough hot water to cover them and set aside for 15 minutes. Once soaked for 15 minutes, drain and squeeze excess water.
Toss the soya chunks in a tablespoon of corn flour.
Heat a tablespoon oil in a large pan and add the soya chunks. Fry them on all sides for 3-4 minutes and remove from pan. In the same pan, add remaining oil and stir fry garlic, ginger, green chillies and onion on high heat for 2-3 minutes.
Add the bell peppers and soya chunks in the pan and toss well.
In a bowl, whisk together soy sauce, chilli sauce, ketchup, remaining cornflour and 3/4th cup water and add this mixture to the pan. Keep stirring till the sauce comes to a boil and thickens. Turn off the flame, top with sliced green onions and serve hot.