Preheat your oven to 400°F (200°C) for a crispy texture.
In a mixing bowl, combine the chicken pieces with salt and ground pepper.
Set up a breading station with cornstarch in one bowl and beaten eggs in another.
Coat each chicken piece in cornstarch, then dip into the beaten eggs, and place on the baking sheet.
Drizzle oil over the coated chicken and bake for 20-25 minutes until golden brown, turning halfway.
Prepare the orange sauce by combining brown sugar, orange juice, rice vinegar, soy sauce, garlic, red chili flakes, and orange zest in a saucepan. Simmer over medium heat.
Mix 1 teaspoon of cornstarch with a tablespoon of water to create a slurry and add to the simmering sauce to thicken.
Toss the baked chicken in the prepared orange sauce until fully coated.
Serve the Baked Orange Chicken on a platter and garnish with chopped green onions.
