In a large bowl, combine the flour, salt, and black pepper. Dredge the chicken pieces in the flour mixture, shaking off any excess.

Dip the floured chicken pieces into the beaten eggs, then coat them with panko breadcrumbs, pressing gently to adhere.

In a medium saucepan over medium heat, combine the orange juice, sugar, soy sauce, rice vinegar, cornstarch, garlic powder, and ginger powder. Stir until the mixture thickens, about 5-7 minutes. Remove from heat and set aside.

In a large skillet or deep fryer, heat the vegetable oil over medium-high heat. Fry the chicken pieces in batches until golden brown and crispy, about 4-5 minutes per side. Remove and drain on paper towels.

In a large bowl, toss the crispy chicken with the orange sauce until evenly coated.

Serve the orange chicken hot, garnished with chopped green onions and sesame seeds.