Cook the rice and add it into a large resealable freezer bag.
Add the chopped onion, celery, carrots, water chestnuts, and peas, then the cooked chicken.
Pour garlic cloves, oyster sauce, and soy sauce into the bag.
Squish everything together to combine. Remove excess air and seal. Lay flat and freeze.
On the day you want to cook the Chicken Fried Rice, take it out of the freezer and thaw.
Heat in a covered casserole dish in the oven until warm or fry up in a skillet or wok.