Chicken and green bean stir fry - chinese grandma

Ingredients

• 1 1/2 pounds boneless skinless chicken breast
• 1 1/4 pounds green beans
• Cooking oil
• 3 tablespoons soy sauce
• 2 tablespoons dry sherry
• 1 clove garlic
• 2 tablespoons brown sugar
• 1 tablespoon cornstarch
• 1 tablespoon apple cider vinegar (white vinegar or rice vinegar also fine)
• 3 tablespoons soy sauce (Kikkoman is best)
• 1 tablespoon sherry
• Dash sesame oil
• 1/2 teaspoon fresh ginger, grated
• Crushed red pepper flakes, to taste