In a medium-sized bowl, combine all sauce ingredients. Always add the sauce during the final seconds of stir-frying. Because cornstarch can settle into a hard layer at the bottom of the sauce, always give the sauce a vigorous stir before adding it to the wok.

1 teaspoon grated tangerine or orange zest
1/3 cup freshly squeezed tangerine or orange juice
1/4 cup dry sherry or Chinese rice wine
2 tablespoons oyster sauce
1 tablespoon hoisin sauce
1 tablespoon dark sesame oil
2 teaspoons Asian chile sauce
2 teaspoons cornstarch