In a large bowl, combine flour, salt, and pepper. Dredge the chicken pieces in the flour mixture, shaking off any excess. Dip them into the beaten eggs, then coat with panko breadcrumbs. Set aside.

In a medium saucepan over medium heat, combine orange juice, sugar, soy sauce, rice vinegar, garlic, and ginger. Bring to a simmer and cook for about 5 minutes.

In a small bowl, mix cornstarch and water to create a slurry. Slowly add this to the simmering sauce, stirring constantly until the sauce thickens, about 2-3 minutes. Remove from heat and set aside.

In a large skillet or frying pan, heat vegetable oil over medium-high heat. Fry the breaded chicken pieces in batches until golden brown and cooked through, about 5-7 minutes per batch. Drain on paper towels.

In a large bowl, toss the fried chicken with the orange sauce until well coated.

Serve hot, garnished with sliced green onions and sesame seeds.