Mix chicken with garlic, soy sauce, Shaoxing wine, chili, salt, and pepper. Let it rest for 5–10 minutes.
Dust chicken in cornflour. In another bowl, mix remaining flours, salt, pepper, baking powder. Add cold soda water to form a bubbly batter.
Dip chicken into batter and fry in hot oil (170–180°C) for 2–3 mins until golden. Drain on paper towel.
Mix all sauce ingredients in a pan. Simmer on low until thick (3–4 mins). Toss fried chicken in sauce until coated.
Top with sesame seed (optional). Best enjoyed fresh and crispy!