Cook the rice in a saucepan of boiling water for 15–18 minutes or until just tender. Drain, rinse in cold water, drain thoroughly and put into a bowl with the lime rind and juice and toss together. Cover and set aside. Brush the steaks with the sesame oil then cook in a preheated frying pan over a high heat for 1–3 minutes each side, depending on preference. Transfer to a shallow non-metallic dish.
Cut the courgettes and carrots into long thin slices with a vegetable peeler, add to the hot frying pan with the spring onion, garlic, chilli and ginger and fry briefly for 30 seconds. Transfer to the dish with the steak. Add the soy sauce, sherry or water, fish sauce and sugar to the pan and warm gently. Pour over the steak and vegetables, allow to cool, then chill until required.
When ready to serve, transfer the rice to a salad bowl. Add the vegetables and sauce and the torn herbs and toss to combine. Cut the steak into thin slices and arrange on top of the rice salad.