Cut the chicken into bite-sized pieces.
Slice the onion and bell pepper thinly.
Add cooking oil to a pan and stir-fry the chicken.
Once the chicken is cooked, add the onion and bell pepper and stir-fry together.
Season with soy sauce, sugar, and minced garlic.
Serve the fried ingredients over rice.
Finish with chopped scallions and sesame seeds.