1. For the omelette, whisk eggs, fish sauce, water and a generous grinding of black pepper. Heat vegetable oil in a wok over high heat. Once oil is hot, pour in egg mixture. Cook omelette for about 2 minutes or until golden and then flip over. Cook for 10 secs and remove from heat.
2. Slice into thin strips and set aside.
3. Heat another 2 tbsp vegetable oil in the wok and stir fry garlic and onion until fragrant and starting to char. Add prawns and stir fry until just cooked. Add rice and break up with your spatula. Toss through fish sauce and soy sauce. Then toss through omelette, tomatoes and sugar.
4. Stir-fry until well combined. Remove from heat and toss through spring onion and pepper. Serve with lime wedges and cucumber.