Marinate the chicken pieces in soy sauce for 10 minutes.
Coat the marinated chicken with cornstarch evenly.
Heat vegetable oil in a large skillet over medium-high heat.
Add the coated chicken pieces in batches and cook until golden brown.
Remove the chicken and set aside on a plate lined with paper towels.
In the same skillet, reduce heat and add garlic and ginger, sautéing for 1 minute.
Add orange juice, sugar, and sesame oil, stirring to combine.
Bring the sauce to a simmer until it thickens slightly.
Return the chicken to the skillet, tossing to coat in the sauce.
Serve hot, garnished with green onions.