In a small bowl, whisk together chicken broth, soy sauce, rice vinegar, sugar, cornstarch, black pepper, sesame oil, and ginger. Keep whisking until the cornstarch is fully dissolved and you no longer see any white streaks or sediment at the bottom of the bowl. Set it aside. If you skip the thorough whisking, the cornstarch will clump when it hits the hot pan and your sauce will be lumpy instead of smooth.
¾ Cup Chicken Stock, 2 Tablespoon Soy Sauce, 1 Tablespoon Rice Vinegar, 1 Tablespoon Sugar, 1 Tablespoon Cornstarch, 2-3 teaspoons Black Pepper, 1 Teaspoon ground ginger, 2 teaspoons Sesame Oil