Prepare batter according to instructions and refrigerate chicken pieces in the batter for 30-60 minutes.
Heat oil in a large pot or wok to 325°F (162°C).
Add battered chicken to the hot oil in batches, agitating to prevent sticking.
Cook chicken for 4-5 minutes until cooked through, then remove to a rack or paper towels.
Raise oil temperature to 375°F (190°C) and fry chicken again for about 2 minutes until browned.
Prepare orange sauce according to instructions.
Toss fried chicken in sauce until evenly coated, drizzle with toasted sesame oil, and serve immediately.