Add the egg to a shallow bowl and whisk to break up the yolk.
Add the chicken pieces to the egg and toss to combine.
In another shallow bowl, add the cornstarch, salt, and pepper.
Add the chicken pieces from the egg mixture, shaking off some of the excess egg mixture, and toss in the cornstarch mixture.
Add the oil to a large skillet. Add the chicken pieces and cook until golden brown on the outside, about 7-8 minutes, turning halfway.
Add the sliced mini peppers and cook another 4-5 more minutes, tossing frequently.
Add the sauce and cashews, cooking until the sauce has thickened.
Serve topped with diced green onions. Enjoy!