Spray a large nonstick wok or frying pan with cooking spray and heat over a high heat. Pour in the beaten eggs and swirl to coat the base of the pan evenly. Cook for about 1 minute until almost cooked through and just set. Carefully remove the omelette from the pan and drain on kitchen paper.
Roll the omelette into a cigar shape, thinly slice into thin strips and set aside.
Wipe the pan clean with kitchen paper, re-spray with cooking spray and heat over a medium heat. Add the ginger and garlic and stir-fry for 30 seconds. Add the onion and Chinese sausage and stir-fry for about 2–3 minutes until lightly browned and tender. Add the prawns and stir-fry for 30 seconds. Stir in the sugar and rice wine and cook, stirring, for 1 minute.
Add the rice, reserved omelette strips, oyster sauce, spring onions, soy sauce and sesame oil to the pan and toss together for about 3–4 minutes until the rice is piping hot. Divide the rice mixture between 4 warmed bowls and serve immediately.