Because of the amount of fat in otoro, the exterior fries up crisp like bacon, while the interior melts like butter into a decadent, creamy morsel of tuna. Seasoning the cubes of tuna with mojio (sometimes transliterated moshio), an ancient Japanese salt, is the trick to making the otoro so flavorful. That's because mojio is made by boiling seawater with kelp, giving it a light beige color and loads of glutamates, which stimulate the umami taste buds on your tongue. The potent fresh wasabi helps offset the richness of the tuna, giving each bite some fresh horseradish notes, while the fried garlic chips imbue a complex umami and sweetness. When cutting the tuna, if you want them to be perfect cubes, be sure to start with a piece larger than 200 grams so you can trim it to the correct shape, the trimmings make great sashimi.
- Heat a small pot with 1/2 cup vegetable oil in it until it reaches 300 degrees F. And prepare a paper towel lined wire rack.
- Slice the garlic about 1/20-inch thick using a mandoline.
- Fry the garlic until it is not sizzling very much and just starts to brown around the edges. Transfer to the paper towel lined rack to drain.
- Season the cubes of otoro with mojio salt.
- Heat a cast-iron skillet until very hot. Add the cubes of otoro and sear until they brown on one side, then roll to the next side. Repeat until all 6 sides have been seared.
- 2 large cloves garlic
- 1/2 cup vegetable oil
- 200 grams Otoro, cut into 1 1/2 -inch cubes
- mojio salt
- fresh wasabi