For the chilli fish sauce, combine the ingredients in a small bowl.
Heat 2 tablespoons of the vegetable oil in a wok over high heat. Add the onion and garlic and stir-fry for 20 seconds. Add the tomato and stir-fry for half a minute or until the tomato just starts to break down. Add the cabbage and stir-fry for 20 seconds to wilt slightly.
Now add the rice, fish sauce, soy sauce, dark soy sauce, sugar and pepper. Stir-fry until the rice is evenly coated and heated through. Then push the rice to one side of the pan. Add the remaining 1 tablespoon of oil into the empty side. Pour the egg into the oil. Use your spatula to spread it out as it cooks. When just set, toss the rice and egg together. Turn the heat off and toss through the coriander and spring onion.
Serve with the cucumber, lime wedge and chilli fish sauce.
