Cut the chicken breast into bite-sized pieces.
Make the marinade by mixing soy sauce, chili powder, stevia (or sugar), minced garlic, and black pepper.
Coat the chicken breast well with the marinade.
Heat cooking oil in a pan and add the chicken breast.
Cook the chicken breast evenly on both sides over medium heat.
Flip the pieces often so the marinade soaks in well and cooks evenly.
Transfer to a plate and serve.