In a medium bowl, combine soy sauce, sugar and garlic. Add chicken pieces and stir to coat with mixture.
In a separate bowl, whisk chicken broth into cornstarch and set aside.
In a wok or sauté pan, heat 2 tablespoons of peanut oil in a wok until almost smoking hot.
Add broccoli and red pepper strips, tossing and stirring constantly for 3 minutes. Add onion and stir-fry 3 minutes. Add remaining 1 tablespoon oil, chicken and soy sauce mixture; stir-fry for another 7 or so minutes, or until chicken is tender and fully cooked.
Stir broth and cornstarch mixture until cornstarch dissolves; add to skillet. Cook, stirring 1 to 2 minutes, or until thickened. Stir in cashew halves and serve.
Servings: 4