If serving with rice put the rice onto cook, especially is using a rice cooker (my preferred method).
Cut up the brown onion and capsicum. Slice the spring onions. Peel and crush the garlic. Grate the ginger (no need to peel). Deseed and finely chop the chillis.
Measure the tomato sauce, soy sauce, vinegar and chilli sauce into a bowl and mix well.
Put the flour onto a plate or shallow bowl. Add the salt and pepper and mix well. Put the egg onto a plate or shallow bowl and lightly beat.
Cut the chicken to cubes and dip into the egg wash, then toss on the flour and shake off any excess flour. Continue until all the chicken is coated.
Heat up a frying pan with the oil until hot. Add the chicken in batched, cooking until golden brown. Reheat before adding more chicken.
Remove the chicken, add a dash more oil and stir fry the vegetables. Remove from the pan and set aside.
Reheat the pan and add a dash more oil. Add the garlic, chilli and ginger and stir for a few seconds until fragrant. Add the tomato sauces mix and stir well. If the sauce is a little thick you can add a dash of water.
Add the chicken and vegetables back into the pan and stir until coated in sauce and heated through.
Serve with rice and garnish with spring onions. Delicious!