For the Beef:

• 1 pound flank steak or sirloin, thinly sliced against the grain
• 2 tablespoons soy sauce
• 1 tablespoon cornstarch

For the Stir-Fry:

• 2 tablespoons vegetable oil
• 1 red bell pepper, sliced
• 1 green bell pepper, sliced
• 1 medium onion, sliced
• 3 garlic cloves, minced
• 1 tablespoon fresh ginger, grated
• ¼ cup low-sodium soy sauce
• 2 tablespoons oyster sauce
• 1 tablespoon rice vinegar
• 1 tablespoon brown sugar
• ½ cup beef broth
• 1 teaspoon sesame oil
• 1 tablespoon cornstarch mixed with 2 tablespoons water (slurry)
• sesame seeds and sliced green onions for garnish