Chinese Vegetable Stir-Fry - Once Upon a Chef

Ingredients

• ⅓ cup soy sauce
• 3 tablespoons water
• 2 tablespoons dry sherry or Chinese rice wine
• 1 teaspoon sesame oil
• 2 teaspoons sugar
• 1 tablespoon cornstarch
• ¼ teaspoon red pepper flakes
• ¼ teaspoon dry mustard
• 2 tablespoons vegetable oil
• 1 pound broccoli, cut into 1-inch florets (or ¾ pound florets)
• 7 ounces shiitake mushrooms, stems removed and thinly sliced
• 1 red bell pepper, thinly sliced
• 3 cloves garlic, finely chopped
• 3 scallions, thinly sliced, white/light green and dark green parts separated
• 1 tablespoon grated fresh ginger (see note)