Prepare the eggs: In a skillet or wok, heat 1 tablespoon of olive oil over medium heat. Add the beaten eggs and cook, stirring gently, until scrambled and just set. Remove from the skillet and set aside.

Sauté the aromatics: In the same skillet, add 1 tablespoon of olive oil and sauté the diced onion and minced garlic for 1-2 minutes until fragrant and slightly softened.

Stir-fry the vegetables: Add the remaining 2 tablespoons of olive oil to the skillet, then add the shredded cabbage and matchstick carrots. Stir-fry for about 5-7 minutes, or until the cabbage and carrots are tender but still crisp.

Add the sauce: In a small bowl, mix the light soy sauce, dark soy sauce, oyster sauce, and sugar. Pour this sauce over the cabbage and carrot mixture, stirring well to coat the vegetables evenly. Add salt to taste if needed.

Combine and finish: Return the scrambled eggs to the skillet and toss everything together for another 1-2 minutes until well combined and heated through.

Serve: Transfer the stir-fry to a serving dish and enjoy warm as a side dish or light main course.