Marinate the Chicken: Pat the chicken chunks dry and place them in a large bowl. Add egg whites, both soy sauces, Shaoxing wine, and cornstarch. Mix until evenly coated. Cover and marinate: Minimum: 1 hour, Best: Overnight (refrigerated).
Prepare the Dry Coating: In a bowl, combine flour, cornstarch, salt, and baking powder. Drain excess marinade from the chicken, then toss generously in the flour mix. Shake off excess flour and fry immediately.
Deep-Fry Until Crispy: Heat oil to 175°C / 350°F. Fry chicken in batches for about 4 minutes, until golden and crisp. Remove and drain on a rack or paper towels. Tip: Do not overcrowd. Temperature control is key — never let the oil smoke.
Prepare the Sauce: Combine all sauce ingredients in a small bowl. Bring to a boil briefly to dissolve the sugar and activate the cornstarch. You can batch this sauce and freeze it in portions.
Toss with Aromatics and Sauce: Heat 1 tbsp oil in a wok or pan over medium heat. Sauté ginger, garlic, scallion, and dried chilies until fragrant (15–30 seconds). Add the measured sauce. It will boil almost immediately. Add fried chicken and toss quickly until the sauce clings and disappears. Remove from heat and serve at once.
