Preheat oven to 400 degrees F. Coat a baking sheet with non-stick cooking spray and set aside.
Add flour, onion powder, salt, and pepper to a gallon-sized ziptop food storage bag. Seal and shake to combine.
Open the bag and add chicken pieces. Seal again and shake until all the chicken is coated with flour.
Transfer chicken to a bowl or small baking sheet. Discard excess flour. In a second bowl, beat the eggs. To a third bowl, add the bread crumbs.
Coat a few chicken pieces in the eggs and then place chicken in the bread crumbs. Turn the chicken until it's coated all over in bread crumbs. Transfer chicken to the prepared baking sheet and repeat until all the chicken is breaded.
Bake for 15 minutes until breading is golden brown and chicken is cooked through.
While the chicken cooks, make the sauce. To a medium saucepot, add garlic ginger, orange juice, marmalade, brown sugar, ketchup, orange zest, soy sauce, sesame oil, rice wine vinegar, and red pepper flakes. Cook over medium heat, whisking occasionally until sauce has thickened.
Once the chicken is cooked, add to saucepot in batches and stir to coat chicken. Transfer sauced chicken to a serving bowl and repeat with remaining pieces.
Serve warm with green onions sprinkled on top and extra red pepper flakes, if you want some more heat.