1.Whisk garlic, cornflour, zest, stock, juice and soy sauce in a medium jug until well combined. Set aside.
2.Heat a wok or large frying pan over high heat. Add oil; swirl to coat surface. Add chicken in batches, stir-fry for 4-5 minutes or until cooked. Remove chicken from wok.
3.Reheat wok. Add carrot; stir-fry for 3 minutes or until just starting to soften. Add snow peas; stir-fry for 2 minutes. Add water chestnuts and chicken; stir-fry for 2 minutes or until hot.
4.Add lemon mixture; stir-fry for 2 minutes or until sauce thickens. Add rice; stir-fry for 3 minutes or until rice is hot. Serve fried rice sprinkled with onion.
For best results, cook rice a day ahead, then refrigerate. This will help keep grains separate when stir-frying.