In a few minutes, your sauce will thicken and be ready to use both hot and at room temperature.
History and origins
It is likely that eel sauce is of Japanese origin and was created to season and flavour grilled eel, one of the typical dishes of the Land of the Rising Sun. Thanks to its flavour, eel sauce enhances the natural flavour of eel and that is why over the years it has been called 'eel sauce'.
Once ready, eel sauce can be transferred to a kitchen bottle with a narrow spout so you can easily decorate dishes. To increase its density you can add a teaspoon of cornstarch and mix well during cooking. If you don't have mirin, a Japanese rice wine, you can use water, or also orange juice to get a more acidic sauce with a different flavour.