Resembling a long slender eel, belt fish can also be sold as silver scabbard fish or under one of its Japanese names -- tachiuo -- which means “great sword fish.” You can present delicately flavored tachiuo in sushi and sashimi, or cook this shiny, metallic-silver fish swiftly by grilling or pan-frying. Season belt fish with a light hand so that you don’t overwhelm its natural sweetness.
Coat your grill rack or a fish basket with nonstick cooking spray. Heat the grill to medium-high.
Season both sides of the belt fish with salt and pepper.
Place the tachiuo onto the hot, oiled grill. Sprinkle fresh lemon juice on top of the fish.
Sear the fish for one minute per side if you prefer your tachiuo very rare. Cook it for five minutes per every half-inch of thickness if you prefer it completely cooked through. The U.S. Department of Agriculture recommends cooking fish to an internal temperature of 145 degrees Fahrenheit. But since tachiuo is traditionally eaten raw, you may serve it at a lower temperature if you have purchased it fresh from a reputable fishmonger.
Pan-Frying Belt Fish
Coat a skillet with olive oil, or whichever type of oil you prefer. Heat the olive oil over medium-high heat until the surface develops a shimmer.
Place the belt fish on the hot oil and sprinkle a generous amount of salt, pepper and minced garlic on top. Sear the outside of the fish or cook it for five minutes per half inch, depending on the level of doneness you prefer.
Turn the fish halfway through the cooking time with tongs to avoid puncturing it. Splash a bit of dry white wine or rice vinegar over the fish, standing back so you don’t get splattered with hot oil. Add a handful of chopped green onions and cook the tachiuo for the same amount of time you cooked it on the other side.