Prepare Panda Express Lemon Sauce according to the recipe in the Box below. Set aside.
In a large bowl, add beaten egg, salt, white pepper and 1 tablespoon oil. Mix well with a whisk.
Add chicken pieces. Stir to coat completely.
In medium bowl, add flour and 1/2 cup cornstarch. Stir to mix well.
Remove chicken pieces from egg wash, allowing excess to drip off, and add to the flour mixture. Toss to coat.
Pour enough oil for deep frying in a wok, large sauce pan or deep fryer.
Heat oil to 375°F.
Working with just a few pieces at a time so as not to crowd, carefully add chicken to the hot oil. Fry for 4 - 5 minutes until golden crisp. Do not overcook.
Remove chicken pieces to a paper towel-covered plate to drain. Keep warm.
Repeat until all chicken pieces are cooked.
Pour out oil. Wipe out wok or sauce pan with a paper towel (If you used a deep fryer, get out a wok or sauce pan for these next steps).
Heat wok or sauce pan for 15 seconds over high heat. Lower to medium high heat.
Add reserved 1 tablespoon oil.
Add ginger and garlic. Stir fry until fragrant, about 10 seconds.
Add red pepper flakes and green onions, stirring for a few seconds.
Add rice wine, stirring for a few seconds.
Add prepared Panda Express Lemon Sauce. Bring to a boil.
Add cooked chicken, stirring until well incorporated.
Stir reserved 1 tablespoon cornstarch into 1/4 cup water. Add to wok.
Heat, stirring constantly, until sauce has thickened.
Remove from heat and stir in toasted sesame oil.
Serve immediately over rice or noodles.