In a small bowl, whisk together first 6 ingredients (soy sauce through salt and pepper) and set aside.
In a large skillet, toast cashews on low-medium heat until golden brown, stirring frequently.
Transfer to a small bowl and set aside.
Raise skillet to medium high heat and add 1 tablespoon sesame oil. Add beef and cook for 7
minutes,stirring frequently. Move beef to the side of the skillet and add remaining sesame oil, peppers, zucchini and snow peas to the center of skillet. Cook vegetables for 5 minutes, stirring frequently.
Stir beef and cashews into vegetables, pour the sauce over and cook for 4 minutes or until vegetables are tender and sauce has thickened, stirring frequently.
Garnish with green onions and serve hot.