Heat wok or large frying pan until very hot. Add peanut oil then beaten eggs and stir fry until set. Cut the egg up as you go with a spatula. Add the prawns and stir fry for one minute. Tip the cooked egg and prawn mix out onto a plate and put aside.
Place the wok back on the heat. Add more peanut oil. Tip in the cooked rice, capsicum and mushrooms and stir. As you stir keep breaking up the rice. Stir fry for about 3 minutes.
Now add the cooked egg and prawn mixture and stir well.
Add the spring onions, soy sauce, fish sauce and sugar and stir well. Taste for seasoning.