Heat oil in a wok or skillet, such as a cast iron skillet, over medium-high heat.
Place the cubed chicken in a large bowl.
In a small bowl stir together cornstarch, salt pepper, and garlic powder.
Add the seasoned cornstarch to the bowl with the chicken and toss until all pieces of chicken are evenly coated with the seasoned cornstarch.
Add the chicken to the hot wok or skillet and cook until lightly browned.
Add the red and green bell peppers and cook for about 5 minutes or until peppers are softened.
Add cashews and cook for about 2 minutes.
Meanwhile, stir together all sauce ingredients in a small bow. Pour the sauce over the cashew chicken in the wok or skillet and cook for about 5 minutes. The sauce should thicken.
Garnish with chopped green onions and sesame seeds.
Serve the Spicy Chinese Cashew Chicken over rice. Enjoy!