Pre-heat the oven to 180ºC. Line a large baking tray with greaseproof paper and spray with low calorie cooking spray.
For the salt and pepper mix: Place a small frying pan over a low heat and add the sea salt. Toast the sea salt in the frying pan for 1 - 2 minutes, stirring, until lightly golden in colour.
Place the toasted sea salt in a small bowl and stir in the sweetener, Chinese five spice powder, chilli flakes and white pepper.
Place the lightly beaten egg on a plate and the breadcrumbs on another plate.
Dip the chunks of chicken in the egg, turning to coat all over, then dip in the breadcrumbs and coat well.
Place the breaded chicken on the baking tray and sprinkle the salt and pepper mixture over, turning to sprinkle on all sides. Spray with low calorie cooking spray.
Place in the oven for 25 - 30 minutes, turning once, until the chicken is golden and thoroughly cooked through. Test that the chicken is cooked by cutting a piece in half, the juices should run clear and there should be no signs of pinkness.
Place a small frying pan on a medium heat and spray with low calorie cooking spray. Add the green pepper, red pepper and chilli and fry for 2-3 minutes, stirring. Add the spring onion and cook for a further 1-2 minutes, stirring well.
Sprinkle the vegetable mixture over the cooked chicken nuggets and serve at once.