Combine the chicken with 1 tablespoon light soy sauce, 1 tablespoon Shaoxing wine, 1 teaspoon toasted sesame oil, and ¼ teaspoon ground white pepper. Let it stand for 10–20 minutes, then beat in the egg just before coating.

Mix 75 g / ½ cup cornstarch with 30 g / ¼ cup plain flour in a bowl. Add the chicken and toss thoroughly, shaking off excess coating so the crust stays crisp rather than overly thick.

Heat approximately 1 litre / 4 cups neutral oil to 175–180°C / 350–355°F. Use a thermometer when possible, since cool oil makes greasy chicken and overheated oil can burn the coating before the chicken cooks.

Fry the chicken in small batches for approximately 4–6 minutes, turning occasionally. Cook until golden brown and confirm that the thickest pieces reach at least 74°C / 165°F internally, then drain on a wire rack.

Combine 120 ml / ½ cup fresh lemon juice, 120 ml / ½ cup chicken stock, 100 g / ½ cup sugar, 1 tablespoon soy sauce, 1 tablespoon rice vinegar, lemon zest, garlic, and ginger in a saucepan. Bring the mixture to a simmer and cook for 1–2 minutes.

Stir 2 teaspoons cornstarch with 2 tablespoons cold water to make a smooth slurry. Whisk it into the simmering sauce and cook for 30–60 seconds, until glossy and lightly thickened.

Add the fried chicken to the sauce and toss briefly, just until every piece is coated. Serve immediately with steamed white rice or fried rice, adding lemon slices, scallions, or toasted sesame seeds if desired.