Heat oil in a nonstick pan over median-high heat, stir in the ham, red onion, celery, carrot and sweet peas, cook for 4-5 minutes until the celery and carrot have turned soft.
Add the cooked white rice into the pan, keep stirring to make sure the rice is mixed well with all the ingredients and is heat evenly, cook for 3-4 minutes until the rice is heat through.
Evenly pour the egg over the rice, stir fry for about 1 minutes until the egg has turned solid.
Toss in the salt, soy sauce and sesame oil, cook for another 1-2 minutes.