- Reserved eel broth
- Remaining eel bones and heads
- 50ml Soy sauce
- 20ml Sake
- 20g Sugar
- 50ml Mirin
- Clean the eel heads by removing the gills and wash off any blood in the head and bones.
- Dry on a paper towel before placing on a metal tray.
- Blowtorch the head and bones until nicely charred.
- Dissolve the soy sauce, sake, sugar and mirin in the reserved eel broth.
- Add in the eel bones and heads.
- When just about simmering, flambé the sauce to burn off the alcohol and add a smokey flavour.
- Skim off any foam and cum that rises to the surface.
- Boil for 20 minutes before removing off the heads and bones.
- Reduce to your desired thickness, about 1/8th of the original volume is usually thick enough.
- Spoon the sauce over Anago and rice to make an Anago rice bowl (Anago-don/穴子丼) or brush onto Anago nigiri.
When eating Unagi (Unagi-don/鰻丼) and anago (Anago-don/穴子丼) rice bowls, There are special ladles used pour just the right amount of sauce over the rice bowls. These ladles are literally translated as Unagi Sauce Hanging Press (unagitarekakepuresu/うなぎタレ掛け プレス). They are uncommon outside of Japan and in my opinion completely unnecessary in a home kitchen. Most high end Anago and Unagi establishments in Japan also offer takeaway bento boxes which are beautifully decorated and customised to each restaurant. This is something seldom found in high end Japanese restaurants.