1. In a medium bowl combine orange zest, juice,soy sauce, vinager and cornstarch, set stir fry sauce aside.
2. In a large non stick skillet heat 1tsp oil over medium heat.
3. Working in 2 batches cook pork until browned on one side 1-2 minutes (pork will cook more later).
4. Transfer to a plate and set aside.
5. In same skillet add remaining oil, garlic and scallion whites ,cook stirring occasionally until scallions wilt 1-2 minutes.
6. Add broccoli and 1/2 cup water, cover and cook until broccoli is crisp tender and water has evaporated, 2-4 minutes.
7. Add pork (with any juices) and stir fry sauce to skillet.
8. Cook stirring, until pork is cooked through and sauce has thickened 1-2 minutes.
9. Top with scallions greens.