Marinate fish cubes with maida, cornflour, ginger garlic paste, pepper powder, half of chilli paste, salt & egg white. Make sure that fish pieces are fully covered with this marinade. Keep it for half an hour & deep fry.
For Gravy
Heat oil in a pan. Add chopped garlic, ginger, green chilli, onion, capsicum & spring onion accordingly & stir.After that add fish pieces. Add remaining red chilli paste. ( All this has to be done in high flame). Add soyasauce & stir. Add some water. Add cornflour paste & keep for 3 more minutes. Garnish with sliced tomatoes.
Notes
Red chilli paste - There are 2 ways of making red chilli paste. Remove the seeds of red chillies & soak it in vinegar for 24 hrs.Grind it. Stir the paste in oil for sometime.Add some vinegar to kashmiri chilli powder & mix well.