Prepare brown rice.
Finely chop chicken breast, onion, and bell pepper.
Heat olive oil in a pan and stir-fry the chicken breast.
Add the onion and bell pepper to the pan and stir-fry together.
Add the brown rice and mix well with the other ingredients while stir-frying.
Top with low-fat mozzarella cheese, cover with a lid, and let the cheese melt.
Serve the finished diet cheese rice in a bowl.