Make batter: Mix flour, cornstarch, and egg to create a smooth batter.
Coat pork: Dip each pork cube evenly into the batter.
Heat oil: Heat oil to 175°C (350°F).
Fry pork: Deep fry pork until golden and crispy, about 4-5 minutes. Remove and drain.
Make sauce: In a bowl, mix sugar, vinegar, ketchup, soy sauce, and a little water.
Stir-fry aromatics: Heat 1 tbsp oil, add minced garlic and vegetables. Stir-fry for 30 seconds.
Add sauce: Pour in the sauce mixture and bring to a boil.
Combine: Add fried pork pieces, quickly toss to coat evenly.
Serve: Serve immediately with steamed rice.
Tips
Tips: 1) Make sure oil is hot enough before frying; 2) Double-fry for extra crispiness; 3) Add vegetables in order of cooking time; 4) Serve immediately for best texture.