1. Combine sugar, flour, ginger, salt, water, mustard, soy sauce, vinegar and garlic in small bowl. Add chicken. Refrigerate for 30 minutes.
2. Heat 1 tablespoon of oil in a large skillet or wok over medium-high heat. With a slotted spoon, remove chicken from marinade to skillet; reserve marinade. Stir-fry chicken for 3 minutes or just until chicken is cooked through. Remove chicken to plate to keep warm. Wipe out skillet with paper toweling.
3. Heat remaining 1 tablespoon of oil in same skillet over medium heat. Add green onion; stir-fry for 1 minute. Add snow peas and red pepper; stir-fry for 3 minutes. Pour reserved marinade into skillet. Bring to boiling. Add chicken to skillet; cook, stirring, for 2 minutes or until the sauce is bubbly and thickened.