Many of you are familiar with the rich, brown, slightly sweet shoyu-based sauce that is used to baste broiled eel. The sauce is called tsume and is made from very basic ingredients. Commercially prepared tsume may contain some chemical ingredients, including monosodium glutamate, so it is better to prepare your own sauce from scratch using the quick and easy recipe below. This version has no eel flavor because it does not use the leftover eel cooking stock of the traditional recipe.