1. In a glass measuring cup, combine teriyaki sauce with 2 tbsp (25 mL) water. Stir in vinegar, brown sugar, cornstarch and garlic; set aside.
2. In a wok or large nonstick skillet, heat oil over high heat. Add cauliflower and cook, stirring, for 1 minute. Add red pepper and zucchini; cook, stirring, for 2 minutes. Reduce heat to medium. Add teriyaki sauce mixture; cook, stirring, until sauce is slightly thickened. Cover and cook for 1 minute or until vegetables are tender-crisp.