Place the eggs, 1 teaspoon of the sesame oil, the soy sauce and salt in a bowl and whisk lightly to combine.
Heat ½ tablespoon of the groundnut oil in a wok over a high heat until the oil starts to shimmer. Pour in the egg mixture and use a spatula to scramble it for 30–60 seconds, until just cooked, then remove the eggs and set aside.
Return the wok to the hob and heat the remaining oil. Add the prawns, ham, ginger and garlic and stir-fry for 1 minute, until the prawns look pink. Add the spring onions, cold cooked rice, cooked eggs and remaining sesame oil and stir-fry for 1–2 minutes, until the rice is steaming hot.