Heat vegetable oil in a large skillet over medium-high heat. Add chicken pieces and cook for about 5-7 minutes until browned. Remove from skillet.
In the same skillet, combine brown sugar, soy sauce, bourbon (or apple juice), apple cider vinegar, ketchup, garlic powder, ground ginger, crushed red pepper flakes (if using), salt, and black pepper. Stir and bring to a simmer.
Return cooked chicken to the skillet and toss in the sauce. Let it simmer for 10-15 minutes until the sauce thickens slightly.
Serve over cooked rice and garnish with sliced green onions.
