Place the beef on some kitchen towels and pat to dry.
Mix 2 tbsp cornstarch, salt, and pepper with the egg and beat well
Add the beef into the egg mixture and toss to coat well
Heat the oil in a wok or large frying pan over high heat.
Add the beef in small batches and fry until crispy 5-6 minutes, turn 2-3 times
Remove the beef with a slotted spoon to a draining rig and keep it warm
In the work or frying pan, make sure you have a small amount of oil left
Reduce the heat to medium, and add the bell pepper, dried chilies, and onion. Fry for 2-4 minutes, looking for tender-crisp here
While the peppers and onions are cooking, mix the orange zest, juice, soy sauce, sugar, garlic, rice vinegar, and ginger and put to one side. (save a small amount of zest for garnish)
Pour the sauce over the veggies, return the heat to a boil, turn to a simmer, and simmer for 1-2 minutes.
Add the beef back; stir for ~ 1 minute to heat through, and coat. The sauce should be thick and coat the beef.
Serve with rice and garnish with scallions and some additional zest