Prepare the cornflour slurry by mixing 1 heaped tsp cornflour with 50ml cold water
Cut chicken fillets into bite-sized pieces
Dice the white onion and chop the red and green peppers
Heat oil in a wok or large pan over high heat
Add chicken fillets and cook until golden
Add diced onion and cook until softened
Add red and green peppers and stir-fry
Add chicken bouillon and garlic granules, stirring well
Add crushed black peppercorns to taste
Pour in dark soy sauce, light soy sauce, and chicken stock
Bring to a simmer
Add oyster sauce and stir
Pour in cornflour slurry to thicken the sauce
Stir continuously until sauce reaches desired thickness
Adjust black pepper to taste and serve
