Prepare the Chicken: Place chicken pieces in a bowl. Add eggs and mix until coated. In another bowl, stir together flour and cornstarch. Dredge the chicken pieces until fully coated. This layer helps create that crisp finish.
Heat the Oil: Pour oil into a deep pan and heat over medium. Test the oil with one small piece of chicken. It should sizzle gently right away.
Fry the Chicken: Carefully add chicken in batches. Cook until golden and crisp, turning occasionally. Remove and place on a paper towel lined plate. Keep warm while finishing the rest.
Start the Sauce: In a saucepan, combine orange juice, sugar, soy sauce, rice vinegar, orange zest, ginger, garlic, and red pepper flakes. Stir and bring to a gentle simmer.
Thicken the Sauce: Mix cornstarch and water in a small bowl. Slowly pour into the simmering sauce while stirring. Cook until the sauce thickens and turns glossy.
Combine Chicken and Sauce: Add fried chicken pieces to the pan with the sauce. Toss gently so every piece gets coated. Let it simmer briefly so the flavors come together.
Finish and Garnish: Sprinkle sesame seeds and green onions over the chicken. Serve hot while the coating stays crisp.
