Prep your ingredients. Dice your chicken into bite-sized pieces and sprinkle black pepper, salt and cornflour over the chicken and mix. This would be a great time to get your veg and rice going.
Stir fry the red peppers and spring onions over a medium heat for 10 minutes. I cut my red peppers into long strips, though you can dice them into smaller pieces if you like. You could also roast these bell peppers in the oven if you prefer.
Add the chicken, continue to stir until all sides have cooked. Do not fully cook the chicken, it will cook completely when it simmers in the sauce. This process should take another 5-10 minutes depending on your quantities.
Add the homemade teriyaki sauce. Combine the soy sauce, honey, vinegar, water and chilli flakes and mix together in a bowl. Pour this mixture over the chicken and add your ginger and garlic to the pan. Keeping mixing for a further 15 minutes or until the sauce has thickened and the chicken is coated in the teriyaki sauce.