Make the orange sauce. In a medium mixing bowl, add the orange juice, orange zest, soy sauce, oyster sauce, white vinegar, and brown sugar. Mix until combined and set aside.
Prepare the chicken. In a large mixing bowl, add the Chicken Thighs (or breast; cut into 1-inch pieces), Salt, White Pepper, and Egg, and mix until combined. Then toss each chicken piece with Cornstarch (or more if needed) until evenly coated. Set aside.
Fry the chicken. Heat about 1 1/2 inches of Neutral Oil (for frying (vegetable, canola, or peanut)) in a wok or heavy-bottomed pot over medium-high heat until it reaches 365°F (185°C). Gently place the battered chicken in the oil with a spider strainer, working in 3 batches to prevent overcrowding. Fry for about 6-7 minutes, flipping halfway, until golden brown. Remove the chicken with a spider strainer and place it on a wire rack to drain excess oil.
Double fry (optional). For a crispier chicken, increase the heat to 385°F (196°C) and fry the chicken in batches for 2 minutes or until golden brown and crispy. Remove and place on a wire rack to drain excess oil.
Cook the sauce. Heat one tablespoon of Neutral Oil (for frying (vegetable, canola, or peanut)) in a large pan over medium heat. Add the Garlic (finely minced), Ginger (grated), and Chili Flakes (optional) if using. Sauté for about 20 seconds until fragrant. Then add the prepared orange sauce and bring to a simmer, stirring continuously for about 2-3 minutes. Mix a cornstarch slurry using Cornstarch and Water, and slowly whisk it into the sauce until it thickens.
Add chicken and green onion. When the sauce has thickened, turn off the heat, add the fried chicken and Green Onions (diced). Toss to combine.
Serve. Serve immediately with steamed rice and enjoy!
