Prepare the Chicken Batter:
In a mixing bowl, whisk together cornstarch, flour, salt, pepper, and garlic powder.
In another bowl, whisk the egg and water.
Dip each chicken piece into the egg mixture, then coat in the flour mixture.
Fry the Chicken:
Heat 2 inches of vegetable oil in a deep pan to 350°F (175°C).
Fry the chicken in batches until golden brown and crispy, about 4-5 minutes per batch. Drain on paper towels.
Make the Honey Sesame Sauce:
In a saucepan over medium heat, whisk together honey, soy sauce, rice vinegar, sesame oil, garlic, and ginger.
Stir in the cornstarch slurry and cook until the sauce thickens (1-2 minutes). Remove from heat.
Stir-Fry the Vegetables:
In a large skillet or wok, heat 1 tablespoon oil over medium-high heat.
Add bell peppers and green beans, cooking for 3-4 minutes until slightly tender.
Toss Everything Together:
Add the fried chicken to the skillet with vegetables.
Pour the honey sesame sauce over and toss to coat evenly.
Garnish And Serve:
Sprinkle with sesame seeds and green onions.
Serve hot over steamed rice or fried rice.