1. Mix together the eggs, salt and cornstarch and toss the beef in this until well coated.
2. Heat the oil in a wok to 350°F,or until a cube of bread browns in 30 seconds, and stir-fry the beef for 1½ minutes or until crispy. Remove and drain on paper towels.
3. Reheat the oil and deep-fry the carrots for 1½ minutes. Remove and drain on paper towels.
4. Pour off most of the oil, leaving about 1½ tbsp in the bottom of the wok. Reheat, then add the spring onions, chillies and garlic. Stir-fry together for about 30 seconds over the heat then add the sugar, soy sauce and vinegar.
5. Return the meat and carrots to the sauce. Toss over the heat and serve.