1/2 cup hoisin sauce
2/3 cup water
2 T corn starch
1/2 t grated fresh ginger or 1/4 t granulated/powdered ginger
3 T soy sauce
1/2 t salt
1/2 t cracked black pepper
Whisk water and cornstarch in a small bowl; set aside.
Place hoisin sauce, ginger, soy sauce, salt and pepper in a small sauce pan. Turn on stove to medium and heat up contents; add the water-cornstarch mixture. Whisk continuously to avoid curdling at the bottom of pan.
Remove from heat when mixture has thickened.
Use immediately on egg fu yung.