Teriyaki Beef Stir-Fry

Ingredients

• 1 lb beef stir-fry strips (or boneless skinless chicken breasts, thinly sliced)
• 1 tablespoon vegetable oil
• 1 onion chopped
• 3 garlic cloves minced
• 1 tablespoon minced gingerroot (or 1tsp/5 mL ground ginger)
• 3/4 cups beef stock
• 1/4 cup thick teriyaki sauce
• 1 tablespoon cornstarch
• 1 tablespoon rice vinegar
• 1 green onion thinly sliced
• 4 baby bok choy quartered lengthwise
• 2 cups button mushrooms