Cut the thawed chicken breast into bite-sized pieces.
Add one spoonful of olive oil to a pan, put in the chicken breast, and when it starts to brown, add the onion and stir-fry together.
Add the prepared sauce (soy sauce 3, water 2.5-3, allulose 1, mirin 1) and simmer over medium-low heat.
When it has thickened, beat one egg and pour it over the mixture, cover with a lid, and cook for 2-3 minutes.
Serve over rice.