Crack the eggs into a small bowl and beat them together.
Heat a skillet with 1 tablespoon of the oil over medium-high heat. Once the pan is hot, add the beaten eggs and scramble them for about a minute. Transfer the eggs to a dish and turn off the heat.
Drizzle the remaining 2 tablespoons of oil into a wok over high heat. Add the onions and cook them for about 1 to 2 minutes, stirring constantly. Add the mixed vegetables and white parts of the scallions and cook for 2 minutes. Season the vegetables with a pinch of salt.
Add the cooked rice into the pan or wok and cook for several minutes, until the rice is heated through. If there are large clumps of rice, break them apart with the back of your spatula.
Add the soy sauce, five-spice powder, dash of white pepper (if using) and sesame oil and stir to distribute the seasonings. (See note 6) Add the scrambled eggs and stir to mix again. Garnish with remaining sliced scallions. Serve immediately.